Opioids are substances that act on
opioid receptor
Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatostatin r ...
s to produce
morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
-like effects.
Medically they are primarily used for
pain relief
Pain management is an aspect of medicine and health care involving relief of pain (pain relief, analgesia, pain control) in various dimensions, from acute and simple to chronic and challenging. Most physicians and other health professionals pr ...
, including
anesthesia
Anesthesia is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prevention of pain), paralysis (muscle relaxation), ...
.
Other medical uses include suppression of
diarrhea
Diarrhea, also spelled diarrhoea, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin wi ...
, replacement therapy for
opioid use disorder
Opioid use disorder (OUD) is a substance use disorder characterized by cravings for opioids, continued use despite physical and/or psychological deterioration, increased tolerance with use, and withdrawal symptoms after discontinuing opioids. Op ...
, reversing
opioid overdose
An opioid overdose is toxicity due to excessive consumption of opioids, such as morphine, codeine, heroin, fentanyl, tramadol, and methadone. This preventable pathology can be fatal if it leads to respiratory depression, a lethal condition that ca ...
, and suppressing cough.
Extremely potent opioids such as
carfentanil
Carfentanil or carfentanyl, sold under the brand name Wildnil, is a very potent opioid analgesic which is used in veterinary medicine to anesthetize large animals such as elephants and rhinoceroses. It is typically administered in this context ...
are approved only for veterinary use.
Opioids are also frequently used non-medically for their
euphoric
Euphoria ( ) is the experience (or affect) of pleasure or excitement and intense feelings of well-being and happiness. Certain natural rewards and social activities, such as aerobic exercise, laughter, listening to or making music and da ...
effects or to prevent
withdrawal
Withdrawal means "an act of taking out" and may refer to:
* Anchoresis (withdrawal from the world for religious or ethical reasons)
* ''Coitus interruptus'' (the withdrawal method)
* Drug withdrawal
* Social withdrawal
* Taking of money from a ban ...
. Opioids can cause death and have been used for
executions in the United States.
Side effects of opioids may include
itchiness
Itch (also known as pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to be classified as any one type of sensory experience. Itch has many similarities to pain, and while both are unpleasant ...
,
sedation
Sedation is the reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure or diagnostic procedure. Examples of drugs which can be used for sedation include isoflurane, diethyl ether, ...
,
nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
,
respiratory depression
Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide (hypercapnia ...
,
constipation
Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement ...
, and
euphoria
Euphoria ( ) is the experience (or affect) of pleasure or excitement and intense feelings of well-being and happiness. Certain natural rewards and social activities, such as aerobic exercise, laughter, listening to or making music and da ...
. Long-term use can cause
tolerance
Tolerance or toleration is the state of tolerating, or putting up with, conditionally.
Economics, business, and politics
* Toleration Party, a historic political party active in Connecticut
* Tolerant Systems, the former name of Veritas Software ...
, meaning that increased doses are required to achieve the same effect, and
physical dependence
Physical dependence is a physical condition caused by chronic use of a tolerance-forming drug, in which abrupt or gradual drug withdrawal causes unpleasant physical symptoms. Physical dependence can develop from low-dose therapeutic use of certai ...
, meaning that abruptly discontinuing the drug leads to unpleasant withdrawal symptoms. The euphoria attracts recreational use, and frequent, escalating recreational use of opioids typically results in addiction. An
overdose
A drug overdose (overdose or OD) is the ingestion or application of a drug or other substance in quantities much greater than are recommended. or concurrent use with other
depressant drugs like
benzodiazepine
Benzodiazepines (BZD, BDZ, BZs), sometimes called "benzos", are a class of depressant drugs whose core chemical structure is the fusion of a benzene ring and a diazepine ring. They are prescribed to treat conditions such as anxiety disorders, ...
s commonly results in death from respiratory depression.
Opioids act by binding to opioid receptors, which are found principally in the
central
Central is an adjective usually referring to being in the center of some place or (mathematical) object.
Central may also refer to:
Directions and generalised locations
* Central Africa, a region in the centre of Africa continent, also known as ...
and
peripheral nervous system
The peripheral nervous system (PNS) is one of two components that make up the nervous system of bilateral animals, with the other part being the central nervous system (CNS). The PNS consists of nerves and ganglia, which lie outside the brain ...
and the
gastrointestinal tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organ (biology), organs of the digestive syste ...
. These receptors mediate both the
psychoactive
A psychoactive drug, psychopharmaceutical, psychoactive agent or psychotropic drug is a chemical substance, that changes functions of the nervous system, and results in alterations in perception, mood, consciousness, cognition or behavior.
Th ...
and the somatic effects of opioids. Opioid drugs include
partial agonists
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...
, like the anti-diarrhea drug
loperamide
Loperamide, sold under the brand name Imodium, among others,Drugs.co Page accessed September 4, 2015 is a medication used to decrease the frequency of diarrhea. It is often used for this purpose in inflammatory bowel disease and short bowel synd ...
and
antagonists
An antagonist is a character in a story who is presented as the chief foe of the protagonist.
Etymology
The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...
like
naloxegol
Naloxegol (INN; PEGylated naloxol; trade names Movantik and Moventig) is a peripherally acting μ-opioid receptor antagonist developed by AstraZeneca, licensed from Nektar Therapeutics, for the treatment of opioid-induced constipation. It was app ...
for opioid-induced constipation, which do not cross the
blood–brain barrier
The blood–brain barrier (BBB) is a highly selective semipermeable membrane, semipermeable border of endothelium, endothelial cells that prevents solutes in the circulating blood from ''non-selectively'' crossing into the extracellular fluid of ...
, but can displace other opioids from binding to those receptors.
Because opioids are addictive and may result in fatal overdose, most are
controlled substance
A controlled substance is generally a drug or chemical whose manufacture, possession and use is regulated by a government, such as illicitly used drugs or prescription medications that are designated by law. Some treaties, notably the Single C ...
s. In 2013, between 28 and 38 million people used opioids illicitly (0.6% to 0.8% of the global population between the ages of 15 and 65).
In 2011, an estimated 4 million people in the United States used opioids recreationally or were dependent on them.
As of 2015, increased rates of recreational use and addiction are attributed to over-prescription of opioid medications and inexpensive illicit
heroin
Heroin, also known as diacetylmorphine and diamorphine among other names, is a potent opioid mainly used as a recreational drug for its euphoric effects. Medical grade diamorphine is used as a pure hydrochloride salt. Various white and brow ...
. Conversely, fears about overprescribing, exaggerated side effects, and addiction from opioids are similarly blamed for under-treatment of pain.
Terminology
Opioids include ''
opiate
An opiate, in classical pharmacology, is a substance derived from opium. In more modern usage, the term ''opioid'' is used to designate all substances, both natural and synthetic, that bind to opioid receptors in the brain (including antagonis ...
s'', an older term that refers to such drugs derived from
opium
Opium (or poppy tears, scientific name: ''Lachryma papaveris'') is dried latex obtained from the seed capsules of the opium poppy ''Papaver somniferum''. Approximately 12 percent of opium is made up of the analgesic alkaloid morphine, which i ...
, including
morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
itself.
Other opioids are
semi-synthetic and synthetic drugs such as
hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
,
oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
and
fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
; antagonist drugs such as
naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
; and
endogenous peptides such as the
endorphins
Endorphins (contracted from endogenous morphine) are chemical signals in the brain that block the perception of pain and increase feelings of wellbeing. They are produced and stored in an area of the brain known as the pituitary gland.
Hist ...
.
The terms ''opiate'' and ''
narcotic
The term narcotic (, from ancient Greek ναρκῶ ''narkō'', "to make numb") originally referred medically to any psychoactive compound with numbing or paralyzing properties. In the United States, it has since become associated with opiates ...
'' are sometimes encountered as synonyms for opioid. ''Opiate'' is properly limited to the natural
alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...
s found in the resin of the
opium poppy
''Papaver somniferum'', commonly known as the opium poppy or breadseed poppy, is a species of flowering plant in the family Papaveraceae. It is the species of plant from which both opium and poppy seeds are derived and is also a valuable ornamen ...
although some include semi-synthetic derivatives.
''Narcotic'', derived from words meaning 'numbness' or 'sleep', as an American legal term, refers to
cocaine
Cocaine (from , from , ultimately from Quechuan languages, Quechua: ''kúka'') is a central nervous system (CNS) stimulant mainly recreational drug use, used recreationally for its euphoria, euphoric effects. It is primarily obtained from t ...
and opioids, and their source materials; it is also loosely applied to any illegal or controlled psychoactive drug. In some jurisdictions all controlled drugs are legally classified as ''narcotics''. The term can have pejorative connotations and its use is generally discouraged where that is the case.
Medical uses
Pain
The weak opioid
codeine
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...
, in low doses and combined with one or more other drugs, is commonly available
without a prescription and can be used to treat mild pain.
Other opioids are usually reserved for the relief of moderate to severe pain.
Acute pain
Opioids are effective for the treatment of acute
pain
Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...
(such as pain following surgery).
For immediate relief of moderate to severe acute pain, opioids are frequently the treatment of choice due to their rapid onset, efficacy and reduced risk of dependence. However, a new report showed a clear risk of prolonged opioid use when opioid analgesics are initiated for an acute pain management following surgery or trauma. They have also been found to be important in
palliative care
Palliative care (derived from the Latin root , or 'to cloak') is an interdisciplinary medical caregiving approach aimed at optimizing quality of life and mitigating suffering among people with serious, complex, and often terminal illnesses. Wit ...
to help with the severe, chronic, disabling pain that may occur in some terminal conditions such as cancer, and degenerative conditions such as
rheumatoid arthritis
Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are involv ...
. In many cases opioids are a successful long-term care strategy for those with chronic
cancer pain
Pain in cancer may arise from a tumor compressing or infiltrating nearby body parts; from treatments and diagnostic procedures; or from skin, nerve and other changes caused by a hormone imbalance or immune response. Most chronic (long-lasting) pai ...
.
Just over half of all states in the US have enacted laws that restrict the prescribing or dispensing of opioids for acute pain.
Chronic non-cancer pain
Guidelines have suggested that the risk of opioids is likely greater than their benefits when used for most non-cancer chronic conditions including
headaches
Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches.
Headaches can occur as a result of m ...
,
back pain
Back pain is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar area is the most common area ...
, and
fibromyalgia
Fibromyalgia (FM) is a medical condition defined by the presence of chronic widespread pain, fatigue, waking unrefreshed, cognitive symptoms, lower abdominal pain or cramps, and depression. Other symptoms include insomnia and a general hyp ...
. Thus they should be used cautiously in chronic non-cancer pain.
Responses to Okie's perspective: If used the benefits and harms should be reassessed at least every three months.
In treating chronic pain, opioids are an option to be tried after other less risky pain relievers have been considered, including
paracetamol
Paracetamol, also known as acetaminophen, is a medication used to treat fever and mild to moderate pain. Common brand names include Tylenol and Panadol.
At a standard dose, paracetamol only slightly decreases body temperature; it is inferior ...
/acetaminophen or NSAIDs like
ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used for treating pain, fever, and inflammation. This includes painful menstrual periods, migraines, and rheumatoid arthritis. It may also be used to close a patent ductus arte ...
or
naproxen
Naproxen is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain, menstrual cramps, inflammatory diseases such as rheumatoid arthritis, gout and fever. It is taken orally. It is available in immediate and delayed release formulati ...
.
[ ] Some types of chronic pain, including the pain caused by
fibromyalgia
Fibromyalgia (FM) is a medical condition defined by the presence of chronic widespread pain, fatigue, waking unrefreshed, cognitive symptoms, lower abdominal pain or cramps, and depression. Other symptoms include insomnia and a general hyp ...
or
migraine
Migraine (, ) is a common neurological disorder characterized by recurrent headaches. Typically, the associated headache affects one side of the head, is pulsating in nature, may be moderate to severe in intensity, and could last from a few hou ...
, are preferentially treated with drugs other than opioids.
[For information on the use and overuse of opioids to treat migraines, see , which cites
*
*
* ] The efficacy of using opioids to lessen chronic
neuropathic pain
Neuropathic pain is pain caused by damage or disease affecting the somatosensory system. Neuropathic pain may be associated with abnormal sensations called dysesthesia or pain from normally non-painful stimuli (allodynia). It may have continuous ...
is uncertain.
Opioids are contraindicated as a first-line treatment for headache because they impair alertness, bring risk of dependence, and increase the risk that episodic headaches will become chronic.
[, which cites
*
*
*
* ] Opioids can also cause heightened sensitivity to headache pain.
When other treatments fail or are unavailable, opioids may be appropriate for treating headache if the patient can be monitored to prevent the development of chronic headache.
Opioids are being used more frequently in the management of non-malignant
chronic pain
Chronic pain is classified as pain that lasts longer than three to six months. In medicine, the distinction between Acute (medicine), acute and Chronic condition, chronic pain is sometimes determined by the amount of time since onset. Two commonly ...
. This practice has now led to a new and growing problem with addiction and misuse of opioids.
Because of various negative effects the use of opioids for long-term management of chronic pain is not indicated unless other less risky pain relievers have been found ineffective. Chronic pain which occurs only periodically, such as that from
nerve pain
Neuropathic pain is pain caused by damage or disease affecting the somatosensory system. Neuropathic pain may be associated with abnormal sensations called dysesthesia or pain from normally non-painful stimuli (allodynia). It may have continuous ...
,
migraines
Migraine (, ) is a common neurological disorder characterized by recurrent headaches. Typically, the associated headache affects one side of the head, is pulsating in nature, may be moderate to severe in intensity, and could last from a few hou ...
, and
fibromyalgia
Fibromyalgia (FM) is a medical condition defined by the presence of chronic widespread pain, fatigue, waking unrefreshed, cognitive symptoms, lower abdominal pain or cramps, and depression. Other symptoms include insomnia and a general hyp ...
, frequently is better treated with medications other than opioids.
Paracetamol
Paracetamol, also known as acetaminophen, is a medication used to treat fever and mild to moderate pain. Common brand names include Tylenol and Panadol.
At a standard dose, paracetamol only slightly decreases body temperature; it is inferior ...
and
nonsteroidal anti-inflammatory drug
Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...
s including
ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used for treating pain, fever, and inflammation. This includes painful menstrual periods, migraines, and rheumatoid arthritis. It may also be used to close a patent ductus arte ...
and
naproxen
Naproxen is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain, menstrual cramps, inflammatory diseases such as rheumatoid arthritis, gout and fever. It is taken orally. It is available in immediate and delayed release formulati ...
are considered safer alternatives. They are frequently used combined with opioids, such as paracetamol combined with
oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
(
Percocet
Oxycodone/paracetamol, sold under the brand name Percocet among others, is a fixed-dose combination of the opioid oxycodone with paracetamol (acetaminophen), used to treat moderate to severe pain.
In 2020, it was the 69th most commonly prescri ...
) and ibuprofen combined with
hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
(
Vicoprofen), which
boosts the pain relief but is also intended to deter recreational use.
Other
Cough
Codeine
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...
was once viewed as the "gold standard" in cough suppressants, but this position is now questioned. Some recent
placebo
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures.
In general ...
-controlled trials have found that it may be no better than a placebo for some causes including acute cough in children.
Thus, it is not recommended for children.
Additionally, there is no evidence that
hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
is useful in children. Similarly, a 2012 Dutch guideline regarding the treatment of acute cough does not recommend its use.
(The opioid analogue
dextromethorphan
Dextromethorphan (DXM) is a medication most often used as a cough suppressant in over-the-counter cold and cough medicines. It is sold in syrup, tablet, spray, and lozenge forms. In 2022, the FDA approved a formulation of it combined with bu ...
, long claimed to be as effective a cough suppressant as codeine, has similarly demonstrated little benefit in several recent studies.)
Low dose morphine may help chronic cough but its use is limited by side effects.
Diarrhea and constipation
In cases of diarrhea-predominate
irritable bowel syndrome
Irritable bowel syndrome (IBS) is a "disorder of gut-brain interaction" characterized by a group of symptoms that commonly include abdominal pain and or abdominal bloating and changes in the consistency of bowel movements. These symptoms may ...
, opioids may be used to suppress diarrhea.
Loperamide
Loperamide, sold under the brand name Imodium, among others,Drugs.co Page accessed September 4, 2015 is a medication used to decrease the frequency of diarrhea. It is often used for this purpose in inflammatory bowel disease and short bowel synd ...
is a
peripherally selective Peripherally selective drugs have their primary mechanism of action outside of the central nervous system (CNS), usually because they are excluded from the CNS by the blood–brain barrier. By being excluded from the CNS, drugs may act on the rest ...
opioid available
without a prescription used to suppress diarrhea.
The ability to suppress diarrhea also produces constipation when opioids are used beyond several weeks.
Naloxegol
Naloxegol (INN; PEGylated naloxol; trade names Movantik and Moventig) is a peripherally acting μ-opioid receptor antagonist developed by AstraZeneca, licensed from Nektar Therapeutics, for the treatment of opioid-induced constipation. It was app ...
, a peripherally-selective opioid antagonist is now available to treat opioid induced constipation.
Shortness of breath
Opioids may help with
shortness of breath
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing disc ...
particularly in advanced diseases such as cancer and
COPD
Chronic obstructive pulmonary disease (COPD) is a type of progressive lung disease characterized by long-term respiratory symptoms and airflow limitation. The main symptoms include shortness of breath and a cough, which may or may not produce mu ...
among others. However, findings from two recent systematic reviews of the literature found that opioids were not necessarily more effective in treating shortness of breath in patients who have advanced cancer.
Hyperalgesia
Opioid-induced hyperalgesia (OIH) has been evident in patients after chronic opioid exposure.
Adverse effects
Each year 69,000 people worldwide die of opioid overdose, and 15 million people have an opioid addiction.
In older adults, opioid use is associated with increased adverse effects such as "sedation, nausea, vomiting, constipation, urinary retention, and falls". As a result, older adults taking opioids are at greater risk for injury. Opioids do not cause any specific organ toxicity, unlike many other drugs, such as
aspirin
Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic. Specific inflammatory conditions which aspirin is used to treat inc ...
and paracetamol. They are not associated with upper gastrointestinal bleeding and kidney toxicity.
Prescription of opioids for acute low back pain and management of osteoarthritis seem to have long-term adverse effects
According to the
USCDC, methadone was involved in 31% of opioid related deaths in the US between 1999–2010 and 40% as the sole drug involved, far higher than other opioids. Studies of long term opioids have found that many stop them, and that minor side effects were common.
Addiction occurred in about 0.3%.
In the United States in 2016 opioid overdose resulted in the death of 1.7 in 10,000 people.
In the US charts below many deaths involve multiple opioids:
File:US timeline. Opioid deaths.jpg, US yearly deaths from all opioid drugs. Included in this number are opioid analgesics, along with heroin
Heroin, also known as diacetylmorphine and diamorphine among other names, is a potent opioid mainly used as a recreational drug for its euphoric effects. Medical grade diamorphine is used as a pure hydrochloride salt. Various white and brow ...
and illicit synthetic opioids
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid us ...
.[
File:US timeline. Deaths involving other synthetic opioids, predominately Fentanyl.jpg, US yearly deaths involving other ]synthetic opioids
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid us ...
, predominately Fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
.[
File:US timeline. Prescription opioid pain reliever deaths.jpg, US yearly deaths involving prescription opioids. Non-methadone synthetics is a category dominated by illegally acquired ]fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
, and has been excluded.[Overdose Death Rates]
By National Institute on Drug Abuse
The National Institute on Drug Abuse (NIDA) is a United States federal government research institute whose mission is to "advance science on the causes and consequences of drug use and addiction and to apply that knowledge to improve individual a ...
(NIDA).
File:US timeline. Heroin deaths.jpg, US yearly overdose deaths involving heroin.[
]
Reinforcement disorders
Tolerance
Tolerance
Tolerance or toleration is the state of tolerating, or putting up with, conditionally.
Economics, business, and politics
* Toleration Party, a historic political party active in Connecticut
* Tolerant Systems, the former name of Veritas Software ...
is a process characterized by
neuroadaptations that result in reduced drug effects. While
receptor upregulation may often play an important role other mechanisms are also known. Tolerance is more pronounced for some effects than for others; tolerance occurs slowly to the effects on mood, itching, urinary retention, and respiratory depression, but occurs more quickly to the analgesia and other physical side effects. However, tolerance does not develop to constipation or
(the constriction of the pupil of the eye to less than or equal to two millimeters). This idea has been challenged, however, with some authors arguing that tolerance ''does'' develop to miosis.
Tolerance to opioids is attenuated by a number of substances, including:
*
calcium channel blocker
Calcium channel blockers (CCB), calcium channel antagonists or calcium antagonists are a group of medications that disrupt the movement of calcium () through calcium channels. Calcium channel blockers are used as antihypertensive drugs, i.e., as ...
s
*
intrathecal
Intrathecal administration is a route of administration for drugs via an injection into the spinal canal, or into the subarachnoid space so that it reaches the cerebrospinal fluid (CSF) and is useful in spinal anesthesia, chemotherapy, or pain man ...
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
and
zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...
*
NMDA antagonist
NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the ''N''-Methyl-D-aspartate receptor (NMDAR). They are commonly used as anesthetics for animals and humans; the state of anesthesia they induce ...
s, such as
dextromethorphan
Dextromethorphan (DXM) is a medication most often used as a cough suppressant in over-the-counter cold and cough medicines. It is sold in syrup, tablet, spray, and lozenge forms. In 2022, the FDA approved a formulation of it combined with bu ...
,
ketamine
Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a recreational drug. It is one of the safest anesthetics, as, in contrast with opiates, ether, and propofol, it suppresses ne ...
, and
memantine
Memantine is a medication used to slow the progression of moderate-to-severe Alzheimer's disease. It is taken by mouth.
Common side effects include headache, constipation, sleepiness, and dizziness. Severe side effects may include blood clots ...
.
*
cholecystokinin antagonist A cholecystokinin receptor antagonist is a specific type of receptor antagonist which blocks the receptor sites for the peptide hormone cholecystokinin ( CCK).
There are two subtypes of this receptor known at present, defined as CCKA and CCKB (al ...
s, such as
proglumide
Proglumide (Milid) is a drug that inhibits gastrointestinal motility and reduces gastric secretions. It acts as a cholecystokinin antagonist, which blocks both the CCKA and CCKB subtypes. It was used mainly in the treatment of stomach ulcers, ...
* Newer agents such as the
phosphodiesterase inhibitor
A phosphodiesterase inhibitor is a drug that blocks one or more of the five subtypes of the enzyme phosphodiesterase (PDE), thereby preventing the inactivation of the intracellular second messengers, cyclic adenosine monophosphate (cAMP) and cycli ...
ibudilast
Ibudilast (development codes: AV-411 or MN-166) is an anti-inflammatory drug used mainly in Japan, which acts as a phosphodiesterase inhibitor, inhibiting the PDE4 subtype to the greatest extent, but also showing significant inhibition of other P ...
have also been researched for this application.
Tolerance is a physiologic process where the body adjusts to a medication that is frequently present, usually requiring higher doses of the same medication over time to achieve the same effect. It is a common occurrence in individuals taking high doses of opioids for extended periods, but does not predict any relationship to misuse or addiction.
Physical dependence
Physical dependence
Physical dependence is a physical condition caused by chronic use of a tolerance-forming drug, in which abrupt or gradual drug withdrawal causes unpleasant physical symptoms. Physical dependence can develop from low-dose therapeutic use of certai ...
is the physiological adaptation of the body to the presence of a substance, in this case opioid medication. It is defined by the development of withdrawal symptoms when the substance is discontinued, when the dose is reduced abruptly or, specifically in the case of opioids, when an antagonist (''e.g.'',
naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
) or an agonist-antagonist (''e.g.'',
pentazocine
Pentazocine, sold under the brand name Talwin among others, is a painkiller used to treat moderate to severe pain. It is believed to work by activating (agonizing) κ-opioid receptors (KOR) and μ-opioid receptors (MOR). As such it is called an ...
) is administered. Physical dependence is a normal and expected aspect of certain medications and does not necessarily imply that the patient is addicted.
The withdrawal symptoms for opiates may include severe
dysphoria
Dysphoria (; ) is a profound state of unease or dissatisfaction. It is the semantic opposite of euphoria. In a psychiatric context, dysphoria may accompany depression, anxiety, or agitation.
In psychiatry
Intense states of distress and unea ...
, craving for another opiate dose, irritability,
sweating
Perspiration, also known as sweating, is the production of fluids secreted by the sweat glands in the skin of mammals.
Two types of sweat glands can be found in humans: eccrine glands and apocrine glands. The eccrine sweat glands are distr ...
,
nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
,
rhinorrea
Rhinorrhea, rhinorrhoea, or informally runny nose is the free discharge of a thin mucus fluid from the nose; it is a common condition. It is a common symptom of allergies (hay fever) or certain viral infections, such as the common cold or COVID-1 ...
,
tremor
A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, fa ...
, vomiting and
myalgia
Myalgia (also called muscle pain and muscle ache in layman's terms) is the medical term for muscle pain. Myalgia is a symptom of many diseases. The most common cause of acute myalgia is the overuse of a muscle or group of muscles; another likel ...
. Slowly reducing the intake of opioids over days and weeks can reduce or eliminate the withdrawal symptoms.
[ The speed and severity of withdrawal depends on the half-life of the opioid; heroin and morphine withdrawal occur more quickly than ]methadone
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...
withdrawal. The acute withdrawal phase is often followed by a protracted phase of depression and insomnia that can last for months. The symptoms of opioid withdrawal can be treated with other medications, such as clonidine
Clonidine, sold under the brand name Catapres among others, is an α2-adrenergic agonist medication used to treat high blood pressure, ADHD, drug withdrawal ( alcohol, opioids, or nicotine), menopausal flushing, diarrhea, spasticity, and c ...
. Physical dependence does not predict drug misuse or true addiction, and is closely related to the same mechanism as tolerance. While there is anecdotal claims of benefit with ibogaine
Ibogaine is a naturally occurring psychoactive substance found in plants in the family Apocynaceae such as ''Tabernanthe iboga'', ''Voacanga africana'', and ''Tabernaemontana undulata''. It is a psychedelic with dissociative properties.
Prel ...
, data to support its use in substance dependence is poor.
Critical patients who received regular doses of opioids experience Iatrogenic withdrawal as a frequent syndrome.
Addiction
Drug addiction
Addiction is a neuropsychological disorder characterized by a persistent and intense urge to engage in certain behaviors, one of which is the usage of a drug, despite substantial harm and other negative consequences. Repetitive drug use of ...
is a complex set of behaviors typically associated with misuse of certain drugs, developing over time and with higher drug dosages. Addiction includes psychological compulsion, to the extent that the affected person persists in actions leading to dangerous or unhealthy outcomes. Opioid addiction includes insufflation
In religious and magical practice, insufflation and exsufflation are ritual acts of blowing, breathing, hissing, or puffing that signify variously expulsion or renunciation of evil or of the devil (the Evil One), or infilling or blessing with goo ...
or injection, rather than taking opioids orally as prescribed for medical reasons.[
In European nations such as Austria, Bulgaria, and Slovakia, slow-release oral morphine formulations are used in opiate substitution therapy (OST) for patients who do not well tolerate the side effects of buprenorphine or ]methadone
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...
. buprenorphine
Buprenorphine is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection (intravenous and subcutaneous), as a skin patch (transdermal), ...
can also be used together with naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
for a longer treatment of addiction. / In other European countries including the UK, this is also legally used for OST although on a varying scale of acceptance.
Slow-release formulations of medications are intended to curb misuse and lower addiction rates while trying to still provide legitimate pain relief and ease of use to pain patients. Questions remain, however, about the efficacy and safety of these types of preparations. Further tamper resistant medications are currently under consideration with trials for market approval by the FDA.
The amount of evidence available only permits making a weak conclusion, but it suggests that a physician properly managing opioid use in patients with no history of substance use disorder
Substance use disorder (SUD) is the persistent use of drugs (including alcohol) despite substantial harm and adverse consequences as a result of their use. Substance use disorders are characterized by an array of mental/emotional, physical, and ...
can give long-term pain relief with little risk of developing addiction, or other serious side effects.
Problems with opioids include the following:
# Some people find that opioids do not relieve all of their pain.
# Some people find that opioids side effects cause problems which outweigh the therapy's benefit
# Some people build tolerance to opioids over time. This requires them to increase their drug dosage to maintain the benefit, and that in turn also increases the unwanted side effects.
# Long-term opioid use can cause opioid-induced hyperalgesia
Opioid-induced hyperalgesia (OIH) or opioid-induced abnormal pain sensitivity, also called paradoxical hyperalgesia, is generalized pain caused by the long-term use of opioids such as morphine, oxycodone, and methadone. OIH is not necessarily confi ...
, which is a condition in which the patient has increased sensitivity to pain.
All of the opioids can cause side effects. Common adverse reactions in patients taking opioids for pain relief include nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
and vomiting, drowsiness
Somnolence (alternatively sleepiness or drowsiness) is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia). It has distinct meanings and causes. It can refer to the usual state preceding falling asleep ...
, itching, dry mouth, dizziness
Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to disequilibrium or a non-specific feeling, such as giddiness or foolishness.
Dizziness is a common medical c ...
, and constipation
Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement ...
.
Nausea and vomiting
Tolerance to nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
occurs within 7–10 days, during which antiemetics (''e.g.'' low dose haloperidol
Haloperidol, sold under the brand name Haldol among others, is a typical antipsychotic medication. Haloperidol is used in the treatment of schizophrenia, tics in Tourette syndrome, mania in bipolar disorder, delirium, agitation, acute psychosi ...
once at night) are very effective. Due to severe side effects such as tardive dyskinesia, haloperidol is now rarely used. A related drug, prochlorperazine
Prochlorperazine, formerly sold under the brand name Compazine among others, is a medication used to treat nausea, migraines, schizophrenia, psychosis and anxiety. It is a less preferred medication for anxiety. It may be taken by mouth, rectally ...
is more often used, although it has similar risks. Stronger antiemetics such as ondansetron
Ondansetron, sold under the brand name Zofran among others, is a medication used to prevent nausea and vomiting caused by cancer chemotherapy, radiation therapy, or surgery. It is also effective for treating gastroenteritis. It can be given by ...
or tropisetron
Tropisetron is a serotonin 5-HT3 receptor antagonist used mainly as an antiemetic to treat nausea and vomiting following chemotherapy, although it has been used experimentally as an analgesic in cases of fibromyalgia.
It was patented in 1982 ...
are sometimes used when nausea is severe or continuous and disturbing, despite their greater cost. A less expensive alternative is dopamine antagonists such as domperidone and metoclopramide. Domperidone
Domperidone, sold under the brand name Motilium among others, is a dopamine antagonist medication which is used to treat nausea and vomiting and certain gastrointestinal problems like gastroparesis (delayed gastric emptying). It raises the le ...
does not cross the blood–brain barrier
The blood–brain barrier (BBB) is a highly selective semipermeable membrane, semipermeable border of endothelium, endothelial cells that prevents solutes in the circulating blood from ''non-selectively'' crossing into the extracellular fluid of ...
and produce adverse central antidopaminergic effects, but blocks opioid emetic action in the chemoreceptor trigger zone
The chemoreceptor trigger zone (CTZ) is an area of the medulla oblongata that receives inputs from blood-borne drugs or hormones, and communicates with other structures in the vomiting center to initiate vomiting. The CTZ is located within the area ...
. (The drug is not available in the U.S.) Some antihistamines with anticholinergic properties (''e.g.'' orphenadrine or diphenhydramine) may also be effective. The first-generation antihistamine hydroxyzine is very commonly used, with the added advantages of not causing movement disorders, and also possessing analgesic-sparing properties. Δ9-tetrahydrocannabinol
Tetrahydrocannabinol (THC) is the principal psychoactive constituent of cannabis and one of at least 113 total cannabinoids identified on the plant. Although the chemical formula for THC (C21H30O2) describes multiple isomers, the term ''THC'' ...
relieves nausea and vomiting; it also produces analgesia that may allow lower doses of opioids with reduced nausea and vomiting.
* 5-HT3 antagonists (''e.g.'' ondansetron
Ondansetron, sold under the brand name Zofran among others, is a medication used to prevent nausea and vomiting caused by cancer chemotherapy, radiation therapy, or surgery. It is also effective for treating gastroenteritis. It can be given by ...
)
* Dopamine antagonists (''e.g.'' domperidone
Domperidone, sold under the brand name Motilium among others, is a dopamine antagonist medication which is used to treat nausea and vomiting and certain gastrointestinal problems like gastroparesis (delayed gastric emptying). It raises the le ...
)
* Anti-cholinergic antihistamines (''e.g.'' diphenhydramine
Diphenhydramine (DPH) is an antihistamine and sedative mainly used to treat allergies, insomnia, and symptoms of the common cold. It is also less commonly used for tremor in parkinsonism, and nausea. It is taken by mouth, injected into a vein ...
)
* Δ9-tetrahydrocannabinol (''e.g.'' dronabinol
The International Nonproprietary Name Dronabinol, also known as delta-9-tetrahydrocannabinol, or under the trade names Marinol, Syndros, Reduvo and Adversa, is a generic name for the molecule of delta-9-tetrahydrocannabinol in the pharmaceutica ...
)
Vomiting is due to gastric stasis (large volume vomiting, brief nausea relieved by vomiting, oesophageal reflux, epigastric fullness, early satiation), besides direct action on the chemoreceptor trigger zone
The chemoreceptor trigger zone (CTZ) is an area of the medulla oblongata that receives inputs from blood-borne drugs or hormones, and communicates with other structures in the vomiting center to initiate vomiting. The CTZ is located within the area ...
of the area postrema
The area postrema, a paired structure in the medulla oblongata of the brainstem, is a circumventricular organ having permeable capillaries and sensory neurons that enable its dual role to detect circulating chemical messengers in the blood and ...
, the vomiting centre of the brain. Vomiting can thus be prevented by prokinetic agents (''e.g.'' domperidone
Domperidone, sold under the brand name Motilium among others, is a dopamine antagonist medication which is used to treat nausea and vomiting and certain gastrointestinal problems like gastroparesis (delayed gastric emptying). It raises the le ...
or metoclopramide
Metoclopramide is a medication used for stomach and esophageal problems. It is commonly used to treat and prevent nausea and vomiting, to help with emptying of the stomach in people with delayed stomach emptying, and to help with gastroesoph ...
). If vomiting has already started, these drugs need to be administered by a non-oral route (''e.g.'' subcutaneous for metoclopramide, rectally for domperidone).
* Prokinetic agents (''e.g.'' domperidone
Domperidone, sold under the brand name Motilium among others, is a dopamine antagonist medication which is used to treat nausea and vomiting and certain gastrointestinal problems like gastroparesis (delayed gastric emptying). It raises the le ...
)
* Anti-cholinergic agents (''e.g.'' orphenadrine
Orphenadrine (sold under many brand names) is an anticholinergic drug of the ethanolamine antihistamine class; it is closely related to diphenhydramine. It is a muscle relaxant that is used to treat muscle pain and to help with motor control in Pa ...
)
Evidence suggests that opioid-inclusive anaesthesia is associated with postoperative nausea and vomiting.
Patients with chronic pain using opioids had small improvements in pain and physically functioning and increased risk of vomiting.
Drowsiness
Tolerance to drowsiness
Somnolence (alternatively sleepiness or drowsiness) is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia). It has distinct meanings and causes. It can refer to the usual state preceding falling asleep ...
usually develops over 5–7 days, but if troublesome, switching to an alternative opioid often helps. Certain opioids such as fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
, morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
and diamorphine
Heroin, also known as diacetylmorphine and diamorphine among other names, is a potent opioid mainly used as a recreational drug for its euphoric effects. Medical grade diamorphine is used as a pure hydrochloride salt. Various white and brown ...
(heroin) tend to be particularly sedating, while others such as oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
, tilidine
Tilidine, or tilidate (brand names: Tilidin, Valoron, Tetova and Valtran) is a synthetic opioid painkiller, used mainly in Belgium, Bulgaria, Germany, Luxembourg, South Africa and Switzerland for the treatment of moderate to severe pain, both acu ...
and meperidine
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a synthetic opioid analgesic, pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemis ...
(pethidine) tend to produce comparatively less sedation, but individual patients responses can vary markedly and some degree of trial and error may be needed to find the most suitable drug for a particular patient. Otherwise, treatment with CNS stimulants
Stimulants (also often referred to as psychostimulants or colloquially as uppers) is an overarching term that covers many drugs including those that increase activity of the central nervous system and the body, drugs that are pleasurable and inv ...
is generally effective.
* Stimulants (''e.g.'' caffeine
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is mainly used recreationally as a cognitive enhancer, increasing alertness and attentional performance. Caffeine acts by blocking binding of adenosine t ...
, modafinil
Modafinil, sold under the brand name Provigil among others, is a central nervous system (CNS) stimulant medication used to treat sleepiness due to narcolepsy, shift work sleep disorder, and obstructive sleep apnea. While it has seen off-label ...
, amphetamine
Amphetamine (contracted from alpha- methylphenethylamine) is a strong central nervous system (CNS) stimulant that is used in the treatment of attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. It is also commonly used ...
, methylphenidate
Methylphenidate, sold under the brand names Ritalin and Concerta among others, is the most widely prescribed central nervous system (CNS) stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and, to a lesser extent, ...
)
Itching
Itching
Itch (also known as pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to be classified as any one type of sensory experience. Itch has many similarities to pain, and while both are unpleasan ...
tends not to be a severe problem when opioids are used for pain relief, but antihistamines
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ...
are useful for counteracting itching when it occurs. Non-sedating antihistamines such as fexofenadine are often preferred as they avoid increasing opioid induced drowsiness. However, some sedating antihistamines such as orphenadrine
Orphenadrine (sold under many brand names) is an anticholinergic drug of the ethanolamine antihistamine class; it is closely related to diphenhydramine. It is a muscle relaxant that is used to treat muscle pain and to help with motor control in Pa ...
can produce a synergistic pain relieving effect permitting smaller doses of opioids be used. Consequently, several opioid/antihistamine combination products have been marketed, such as ''Meprozine'' (meperidine
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a synthetic opioid analgesic, pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemis ...
/promethazine
Promethazine is a first-generation antihistamine, antipsychotic, sedative, and antiemetic used to treat allergies, insomnia, and nausea. It may also help with some symptoms associated with the common cold and may also be used for sedating people ...
) and ''Diconal'' (dipipanone
Dipipanone (Pipadone) is a strong opioid analgesic drug, used for acute pain by mouth (PO) for adults - initially 10 mg every 6 hours, then increased if necessary up to 30 mg every 6 hours, with the dose to be increased gradually. It is often use ...
/cyclizine
Cyclizine, sold under a number of brand names, is a medication used to treat and prevent nausea, vomiting and dizziness due to motion sickness or vertigo. It may also be used for nausea after general anaesthesia or that which developed from opio ...
), and these may also reduce opioid induced nausea.
* Antihistamines (''e.g.'' fexofenadine
Fexofenadine, sold under the brand name Allegra among others, is an antihistamine pharmaceutical drug used in the treatment of allergy symptoms, such as hay fever and urticaria.
Therapeutically, fexofenadine is a selective peripheral H1 block ...
)
Constipation
Opioid-induced constipation
Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement ...
(OIC) develops in 90 to 95% of people taking opioids long-term. Since tolerance to this problem does not generally develop, most people on long-term opioids need to take a laxative
Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation.
Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...
or enema
An enema, also known as a clyster, is an injection of fluid into the lower bowel by way of the rectum.Cullingworth, ''A Manual of Nursing, Medical and Surgical'':155 The word enema can also refer to the liquid injected, as well as to a device ...
s.
Treatment of OIC is successional and dependent on severity. The first mode of treatment is non-pharmacological, and includes lifestyle modifications like increasing dietary fiber
Dietary fiber (in British English fibre) or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition, and can be grouped generally by the ...
, fluid intake
Drinking is the act of Ingestion, ingesting water or other liquids into the body through the mouth, proboscis, or elsewhere. Humans drink by swallowing, completed by peristalsis in the esophagus. The physiological processes of drinking vary wide ...
(around per day), and physical activity
Physical activity is defined as any voluntary bodily movement produced by skeletal muscles that requires energy expenditure.Global Recommendations on Physical Activity for Health, 2009. World Health Organization. Geneva, Switzerland. Accessed 13/ ...
. If non-pharmacological measures are ineffective, laxative
Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation.
Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...
s, including stool softener
Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation.
Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...
s (''e.g.'', polyethylene glycol
Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular we ...
), bulk-forming laxatives (''e.g.'', fiber supplement
Fibre supplements (also spelled fiber supplements) are considered to be a form of a subgroup of functional dietary fibre, and in the United States are defined by the Institute of Medicine (IOM). According to the IOM, functional fibre "consists o ...
s), stimulant laxative
Laxatives, purgatives, or aperients are substances that loosen human feces, stools and increase defecation, bowel movements. They are used to treat and prevent constipation.
Laxatives vary as to how they work and the side effects they may have. ...
s (''e.g.'', bisacodyl
Bisacodyl (INN) is an organic compound that is used as a stimulant laxative drug. It works directly on the colon to produce a bowel movement. It is typically prescribed for relief of episodic and chronic constipation and for the management of n ...
, senna), and/or enema
An enema, also known as a clyster, is an injection of fluid into the lower bowel by way of the rectum.Cullingworth, ''A Manual of Nursing, Medical and Surgical'':155 The word enema can also refer to the liquid injected, as well as to a device ...
s, may be used. A common laxative regimen for OIC is the combination of docusate and bisacodyl. Osmotic laxative
Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation.
Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...
s, including lactulose
Lactulose is a non-absorbable sugar used in the treatment of constipation and hepatic encephalopathy. It is used by mouth for constipation and either by mouth or in the rectum for hepatic encephalopathy. It generally begins working after 8–12 ...
, polyethylene glycol
Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular we ...
, and milk of magnesia
Magnesium hydroxide is the inorganic compound with the chemical formula Mg(OH)2. It occurs in nature as the mineral brucite. It is a white solid with low solubility in water (). Magnesium hydroxide is a common component of antacids, such as milk ...
(magnesium hydroxide), as well as mineral oil
Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils.
The name 'mineral oil' by itself is imprecise, ...
(a lubricant laxative), are also commonly used for OIC.
If laxatives are insufficiently effective (which is often the case), opioid formulations or regimens that include a peripherally-selective opioid antagonist
An opioid antagonist, or opioid receptor antagonist, is a receptor antagonist that acts on one or more of the opioid receptors.
Naloxone and naltrexone are commonly used opioid antagonist drugs which are competitive antagonists that bind to the o ...
, such as methylnaltrexone bromide
Methylnaltrexone (MNTX, brand name Relistor), used in form of methylnaltrexone bromide (INN, USAN, BAN), is a medication that acts as a peripherally acting μ-opioid receptor antagonist that acts to reverse some of the side effects of opioid dr ...
, naloxegol
Naloxegol (INN; PEGylated naloxol; trade names Movantik and Moventig) is a peripherally acting μ-opioid receptor antagonist developed by AstraZeneca, licensed from Nektar Therapeutics, for the treatment of opioid-induced constipation. It was app ...
, alvimopan
Alvimopan (trade name Entereg) is a drug which behaves as a peripherally acting μ-opioid receptor antagonist. With the limited ability to cross the blood–brain barrier and reach the μ-opioid receptors of the central nervous system, the clin ...
, or naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
(as in oxycodone/naloxone
Oxycodone/naloxone, sold under the trade name Targin and Targinact (in the UK) among others, is a combination pain medication. It is available as modified-release tablets and is taken by mouth.
The oxycodone component is an opioid and is respon ...
), may be tried. A 2018 Cochrane review found that the evidence was tentative for alvimopan, naloxone, or methylnaltrexone bromide. Naloxone by mouth appears to be the most effective. A daily 0.2 mg dose of naldemedine has been shown to significantly improve symptoms in patients with OIC.
Opioid rotation Opioid rotation or opioid switching is the process of changing one opioid to another to improve pain control or reduce unwanted side effects. This technique was introduced in the 1990s to help manage severe chronic pain and improve t ...
is one method suggested to minimise the impact of constipation in long-term users. While all opioids cause constipation, there are some differences between drugs, with studies suggesting tramadol
Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an h ...
, tapentadol
Tapentadol, brand names Nucynta among others, is a centrally acting opioid analgesic of the benzenoid class with a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI). Analgesia occurs wit ...
, methadone
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...
and fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
may cause relatively less constipation, while with codeine
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...
, morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
, oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
or hydromorphone
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...
constipation may be comparatively more severe.
Respiratory depression
Respiratory depression
Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide (hypercapnia ...
is the most serious adverse reaction associated with opioid use, but it usually is seen with the use of a single, intravenous dose in an opioid-naïve patient. In patients taking opioids regularly for pain relief, tolerance to respiratory depression occurs rapidly, so that it is not a clinical problem. Several drugs have been developed which can partially block respiratory depression, although the only respiratory stimulant currently approved for this purpose is doxapram
Doxapram hydrochloride (marketed as Dopram, Stimulex or Respiram) is a respiratory stimulant. Administered intravenously, doxapram stimulates an increase in tidal volume, and respiratory rate.
Mechanism of action
Doxapram stimulates chemorecept ...
, which has only limited efficacy in this application. Newer drugs such as BIMU-8
BIMU-8 is a drug which acts as a 5-HT4 receptor selective agonist. BIMU-8 was one of the first compounds of this class. The main action of BIMU-8 is to increase the rate of respiration by activating an area of the brain stem known as the pre-Bo ...
and CX-546
CX-546 is an ampakine drug developed by Cortex Pharmaceuticals.
It has been proposed as a treatment for schizophrenia. CX-546 was the second drug of note to come out of the Cortex research program, after CX-516, but while it was an improvement o ...
may be much more effective.
* Respiratory stimulants: carotid chemoreceptor Peripheral chemoreceptors (of the carotid and aortic bodies) are so named because they are sensory extensions of the peripheral nervous system into blood vessels where they detect changes in chemical concentrations. As transducers of patterns of va ...
agonists (''e.g.'' doxapram
Doxapram hydrochloride (marketed as Dopram, Stimulex or Respiram) is a respiratory stimulant. Administered intravenously, doxapram stimulates an increase in tidal volume, and respiratory rate.
Mechanism of action
Doxapram stimulates chemorecept ...
), 5-HT4 agonists (''e.g.'' BIMU8
BIMU-8 is a drug which acts as a 5-HT4 receptor selective agonist. BIMU-8 was one of the first compounds of this class. The main action of BIMU-8 is to increase the rate of respiration by activating an area of the brain stem known as the pre-B ...
), δ-opioid agonists (''e.g.'' BW373U86
(+)-BW373U86 is an opioid analgesic drug used in scientific research.
BW373U86 is a selective agonist for the δ-opioid receptor, with approximately 15x stronger affinity for the δ-opioid than the μ-opioid receptor. It has potent analgesic a ...
) and AMPAkines (''e.g.'' CX717
CX717 is an ampakine compound created by Christopher Marrs and Gary Rogers in 1996 at Cortex Pharmaceuticals. It affects the neurotransmitter glutamate, with trials showing the drug improves cognitive functioning and memory.
Approval process
In ...
) can all reduce respiratory depression caused by opioids without affecting analgesia, but most of these drugs are only moderately effective or have side effects which preclude use in humans. 5-HT1A agonists such as 8-OH-DPAT
8-OH-DPAT is a research chemical of the aminotetralin chemical class which was developed in the 1980s and has been widely used to study the function of the 5-HT1A receptor. It was one of the first major 5-HT1A receptor full agonists to be disco ...
and repinotan
Repinotan (BAYx3702), an aminomethylchroman derivative, is a selective 5-HT1A receptor full agonist with high potency and efficacy. It has neuroprotective effects in animal studies, and was trialed in humans for reducing brain injury following h ...
also counteract opioid-induced respiratory depression, but at the same time reduce analgesia, which limits their usefulness for this application.
* Opioid antagonists (''e.g.'' naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
, nalmefene
Nalmefene is an opioid antagonist medication used in the management of opioid overdose and alcohol dependence. It is taken by mouth.
Nalmefene is an opiate derivative similar in both structure and activity to the opioid antagonist naltrexone. ...
, diprenorphine
Diprenorphine (brand name Revivon; former developmental code name M5050), also known as diprenorfin, is a non-selective, high-affinity, weak partial agonist of the μ- (MOR), κ- (KOR), and δ-opioid receptor (DOR) (with equal affinity) which i ...
)
The initial 24 hours after opioid administration appear to be the most critical with regard to life-threatening OIRD, but may be preventable with a more cautious approach to opioid use.
Patients with cardiac, respiratory disease and/or obstructive sleep apnoea are at increased risk for OIRD.
Increased pain sensitivity
Opioid-induced hyperalgesia – where individuals using opioids to relieve pain paradoxically
A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation. It is a statement that, despite apparently valid reasoning from true premises, leads to a seemingly self-contradictory or a logically u ...
experience more pain as a result of that medication – has been observed in some people. This phenomenon, although uncommon, is seen in some people receiving palliative care
Palliative care (derived from the Latin root , or 'to cloak') is an interdisciplinary medical caregiving approach aimed at optimizing quality of life and mitigating suffering among people with serious, complex, and often terminal illnesses. Wit ...
, most often when dose is increased rapidly. If encountered, rotation between several different opioid pain medications may decrease the development of increased pain. Opioid induced hyperalgesia more commonly occurs with chronic use or brief high doses but some research suggests that it may also occur with very low doses.
Side effects such as hyperalgesia and allodynia
Allodynia is a condition in which pain is caused by a stimulus that does not normally elicit pain. For example, bad sunburn can cause temporary allodynia, and touching sunburned skin, or running cold or warm water over it, can be very painful. It i ...
, sometimes accompanied by a worsening of neuropathic pain
Neuropathic pain is pain caused by damage or disease affecting the somatosensory system. Neuropathic pain may be associated with abnormal sensations called dysesthesia or pain from normally non-painful stimuli (allodynia). It may have continuous ...
, may be consequences of long-term treatment with opioid analgesics, especially when increasing tolerance has resulted in loss of efficacy and consequent progressive dose escalation over time. This appears to largely be a result of actions of opioid drugs at targets other than the three classic opioid receptors, including the nociceptin receptor
The nociceptin opioid peptide receptor (NOP), also known as the nociceptin/orphanin FQ (N/OFQ) receptor or kappa-type 3 opioid receptor, is a protein that in humans is encoded by the ''OPRL1'' (opioid receptor-like 1) gene. The nociceptin receptor ...
, sigma receptor
Sigma receptors (σ-receptors) are protein cell surface receptors that bind ligands such as 4-PPBP (4-phenyl-1-(4-phenylbutyl) piperidine), SA 4503 (cutamesine), ditolylguanidine, dimethyltryptamine, and siramesine. There are two subtypes, ...
and Toll-like receptor 4
Toll-like receptor 4 is a protein that in humans is encoded by the ''TLR4'' gene. TLR4 is a transmembrane protein, member of the toll-like receptor family, which belongs to the pattern recognition receptor (PRR) family. Its activation leads to an ...
, and can be counteracted in animal models by antagonists at these targets such as J-113,397
J-113,397 is an opioid drug which was the first compound found to be a highly selective antagonist for the nociceptin receptor, also known as the ORL-1 receptor. It is several hundred times selective for the ORL-1 receptor over other opioid rece ...
, BD-1047
BD-1047 is a sigma receptor antagonist, selective for the σ1 subtype. It has effects in animal studies suggestive of antipsychotic activity and may also be useful in the treatment of neuropathic pain.
More recent studies also suggest a novel r ...
or (+)-naloxone
(+)-Naloxone (dextro-naloxone) is a drug which is the opposite enantiomer of the opioid antagonist drug (−)-naloxone. Unlike (-)-naloxone, (+)-naloxone has no significant affinity for opioid receptors, but instead has been discovered to act as a ...
respectively. No drugs are currently approved specifically for counteracting opioid-induced hyperalgesia in humans and in severe cases the only solution may be to discontinue use of opioid analgesics and replace them with non-opioid analgesic drugs. However, since individual sensitivity to the development of this side effect is highly dose dependent and may vary depending which opioid analgesic is used, many patients can avoid this side effect simply through dose reduction of the opioid drug (usually accompanied by the addition of a supplemental non-opioid analgesic), rotating between different opioid drugs, or by switching to a milder opioid with a mixed mode of action that also counteracts neuropathic pain, particularly tramadol
Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an h ...
or tapentadol
Tapentadol, brand names Nucynta among others, is a centrally acting opioid analgesic of the benzenoid class with a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI). Analgesia occurs wit ...
.
* NMDA receptor antagonist
NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the ''N''-Methyl-D-aspartate receptor (NMDAR). They are commonly used as anesthetics for animals and humans; the state of anesthesia they induce ...
s such as ketamine
Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a recreational drug. It is one of the safest anesthetics, as, in contrast with opiates, ether, and propofol, it suppresses ne ...
* SNRIs such as milnacipran
Milnacipran (trade names Ixel, Savella, Dalcipran, Toledomin) is a serotonin–norepinephrine reuptake inhibitor (SNRI) used in the clinical treatment of fibromyalgia. It is not approved for the clinical treatment of major depressive disorder in ...
* Anticonvulsant
Anticonvulsants (also known as antiepileptic drugs or recently as antiseizure drugs) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of b ...
s such as gabapentin
Gabapentin, sold under the brand name Neurontin among others, is an anticonvulsant medication primarily used to treat partial seizures and neuropathic pain. It is a first-line medication for the treatment of neuropathic pain caused by diabet ...
or pregabalin
Pregabalin, sold under the brand name Lyrica among others, is an anticonvulsant, analgesic and anxiolytic medication used to treat epilepsy, neuropathic pain, fibromyalgia, restless leg syndrome, opioid withdrawal and generalized anxiety disord ...
Other adverse effects
Low sex hormone levels
Clinical studies have consistently associated medical and recreational opioid use with hypogonadism
Hypogonadism means diminished functional activity of the gonads—the testes or the ovaries—that may result in diminished production of sex hormones. Low androgen (e.g., testosterone) levels are referred to as hypoandrogenism and low estrogen ...
(low sex hormone
Sex hormones, also known as sex steroids, gonadocorticoids and gonadal steroids, are steroid hormones that interact with vertebrate steroid hormone receptors. The sex hormones include the androgens, estrogens, and progestogens. Their effects ar ...
levels) in different sexes. The effect is dose-dependent. Most studies suggest that the majority (perhaps as much as 90%) of chronic opioid users develop hypogonadism. A 2015 systematic review
A systematic review is a Literature review, scholarly synthesis of the evidence on a clearly presented topic using critical methods to identify, define and assess research on the topic. A systematic review extracts and interprets data from publ ...
and meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...
found that opioid therapy suppressed testosterone levels in men by about 165 ng/dL (5.7 nmol/L) on average, which was a reduction in testosterone level of almost 50%. Conversely, opioid therapy did not significantly affect testosterone levels in women. However, opioids can also interfere with menstruation
Menstruation (also known as a period, among other colloquial terms) is the regular discharge of blood and mucosal tissue from the inner lining of the uterus through the vagina. The menstrual cycle is characterized by the rise and fall of hor ...
in women by limiting the production of luteinizing hormone
Luteinizing hormone (LH, also known as luteinising hormone, lutropin and sometimes lutrophin) is a hormone produced by gonadotropic cells in the anterior pituitary gland. The production of LH is regulated by gonadotropin-releasing hormone (GnRH) ...
(LH). Opioid-induced hypogonadism likely causes the strong association of opioid use with osteoporosis
Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone ...
and bone fracture
A bone fracture (abbreviated FRX or Fx, Fx, or #) is a medical condition in which there is a partial or complete break in the continuity of any bone in the body. In more severe cases, the bone may be broken into several fragments, known as a '' ...
, due to deficiency in estradiol
Estradiol (E2), also spelled oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of the estrous and menstrual female reproductive cycles. Estradiol is responsible for the development of f ...
. It also may increase pain and thereby interfere with the intended clinical effect of opioid treatment. Opioid-induced hypogonadism is likely caused by their agonism of opioid receptors in the hypothalamus
The hypothalamus () is a part of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamu ...
and the pituitary gland
In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a chickpea and weighing, on average, in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The ...
. One study found that the depressed testosterone
Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testes and prostate, as well as promoting secondar ...
levels of heroin addicts returned to normal within one month of abstinence, suggesting that the effect is readily reversible and is not permanent. , the effect of low-dose or acute opioid use on the endocrine system
The endocrine system is a messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In vertebrates, the hypothalamus is the neu ...
is unclear. Long-term use of opioids can affect the other hormonal systems as well.
Disruption of work
Use of opioids may be a risk factor for failing to return to work.
Persons performing any safety-sensitive task should not use opioids.[, which cites
* ] Health care providers should not recommend that workers who drive
Drive or The Drive may refer to:
Motoring
* Driving, the act of controlling a vehicle
* Road trip, a journey on roads
Roadways
Roadways called "drives" may include:
* Driveway, a private road for local access to structures, abbreviated "drive"
...
or use heavy equipment
Heavy equipment or heavy machinery refers to heavy-duty vehicles specially designed to execute construction tasks, most frequently involving earthwork operations or other large construction tasks. ''Heavy equipment'' usually comprises five e ...
including cranes or forklifts
A forklift (also called lift truck, jitney, hi-lo, fork truck, fork hoist, and forklift truck) is a powered industrial truck used to lift and move materials over short distances. The forklift was developed in the early 20th century by various ...
treat chronic or acute pain with opioids. Workplaces which manage workers who perform safety-sensitive operations should assign workers to less sensitive duties for so long as those workers are treated by their physician with opioids.
People who take opioids long term have increased likelihood of being unemployed. Taking opioids may further disrupt the patient's life and the adverse effects of opioids themselves can become a significant barrier to patients having an active life, gaining employment, and sustaining a career.
In addition, lack of employment may be a predictor of aberrant use of prescription opioids.
Increased accident-proneness
Opioid use may increase accident-proneness
Accident-proneness is the idea that some people have a greater predisposition than others to experience accidents, such as car crashes and industrial injuries. It may be used as a reason to deny any insurance on such individuals.
Early work
The ...
. Opioids may increase risk of traffic accidents and accidental fall
Falling is the action of a person or animal losing stability and ending up in a lower position, often on the ground. It is the second-leading cause of accidental death worldwide and a major cause of personal injury, especially for the old age, ...
s.
Reduced Attention
Opioids have been shown to reduce attention, more so when used with antidepressants and/or anticonvulsants.
Rare side effects
Infrequent adverse reactions in patients taking opioids for pain relief include: dose-related respiratory depression (especially with more potent opioids), confusion, hallucinations
A hallucination is a perception in the absence of an external stimulus that has the qualities of a real perception. Hallucinations are vivid, substantial, and are perceived to be located in external objective space. Hallucination is a combinatio ...
, delirium
Delirium (also known as acute confusional state) is an organically caused decline from a previous baseline of mental function that develops over a short period of time, typically hours to days. Delirium is a syndrome encompassing disturbances in ...
, urticaria
Hives, also known as urticaria, is a kind of skin rash with red, raised, itchy bumps. Hives may burn or sting. The patches of rash may appear on different body parts, with variable duration from minutes to days, and does not leave any long-lasti ...
, hypothermia
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe h ...
, bradycardia
Bradycardia (also sinus bradycardia) is a slow resting heart rate, commonly under 60 beats per minute (BPM) as determined by an electrocardiogram. It is considered to be a normal heart rate during sleep, in young and healthy or elderly adults, a ...
/tachycardia
Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal (su ...
, orthostatic hypotension
Orthostatic hypotension, also known as postural hypotension, is a medical condition wherein a person's blood pressure drops when standing up or sitting down. Primary orthostatic hypertension is also often referred to as neurogenic orthostatic hyp ...
, dizziness, headache, urinary retention, ureteric or biliary spasm, muscle rigidity, myoclonus (with high doses), and flushing (due to histamine release, except fentanyl and remifentanil).[
Both therapeutic and chronic use of opioids can compromise the function of the ]immune system
The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splinte ...
. Opioids decrease the proliferation of macrophage
Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer cel ...
progenitor cells and lymphocyte
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic ad ...
s, and affect cell differentiation (Roy & Loh, 1996). Opioids may also inhibit leukocyte
White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...
migration. However the relevance of this in the context of pain relief is not known.
Interactions
Physicians treating patients using opioids in combination with other drugs keep continual documentation that further treatment is indicated and remain aware of opportunities to adjust treatment if the patient's condition changes to merit less risky therapy.
With other depressant drugs
The concurrent use of opioids with other depressant drugs such as benzodiazepines
Benzodiazepines (BZD, BDZ, BZs), sometimes called "benzos", are a class of depressant drugs whose core chemical structure is the fusion of a benzene ring and a diazepine ring. They are prescribed to treat conditions such as anxiety disorders, i ...
or ethanol increases the rates of adverse events and overdose. despite this, opioids and benzodiazepines are concurrently dispensed in many settings. As with an overdose of opioid alone, the combination of an opioid and another depressant may precipitate respiratory depression often leading to death. These risks are lessened with close monitoring by a physician, who may conduct ongoing screening for changes in patient behavior and treatment compliance.
Opioid antagonist
Opioid effects (adverse or otherwise) can be reversed with an opioid antagonist such as naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
or naltrexone
Naltrexone, sold under the brand name Revia among others, is a medication primarily used to manage alcohol or opioid use disorder by reducing cravings and feelings of euphoria associated with substance use disorder. It has also been found t ...
. These competitive antagonist
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of recep ...
s bind to the opioid receptors with higher affinity than agonists but do not activate the receptors. This displaces the agonist, attenuating or reversing the agonist effects. However, the elimination half-life
Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the bl ...
of naloxone can be shorter than that of the opioid itself, so repeat dosing or continuous infusion may be required, or a longer acting antagonist such as nalmefene
Nalmefene is an opioid antagonist medication used in the management of opioid overdose and alcohol dependence. It is taken by mouth.
Nalmefene is an opiate derivative similar in both structure and activity to the opioid antagonist naltrexone. ...
may be used. In patients taking opioids regularly it is essential that the opioid is only partially reversed to avoid a severe and distressing reaction of waking in excruciating pain. This is achieved by not giving a full dose but giving this in small doses until the respiratory rate has improved. An infusion is then started to keep the reversal at that level, while maintaining pain relief. Opioid antagonists remain the standard treatment for respiratory depression following opioid overdose, with naloxone being by far the most commonly used, although the longer acting antagonist nalmefene may be used for treating overdoses of long-acting opioids such as methadone, and diprenorphine is used for reversing the effects of extremely potent opioids used in veterinary medicine such as etorphine and carfentanil. However, since opioid antagonists also block the beneficial effects of opioid analgesics, they are generally useful only for treating overdose, with use of opioid antagonists alongside opioid analgesics to reduce side effects, requiring careful dose titration and often being poorly effective at doses low enough to allow analgesia to be maintained.
Naltrexone does not appear to increase risk of serious adverse events, which confirms the safety of oral naltrexone. Mortality or serious adverse events due to rebound toxicity in patients with naloxone were rare.
Pharmacology
Opioids bind to specific opioid receptor
Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatostatin r ...
s in the nervous system
In biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes th ...
and other tissues. There are three principal classes of opioid receptors, μ, κ, δ (mu, kappa, and delta), although up to seventeen have been reported, and include the ε, ι, λ, and ζ (Epsilon, Iota, Lambda and Zeta) receptors. Conversely, σ (Sigma
Sigma (; uppercase Σ, lowercase σ, lowercase in word-final position ς; grc-gre, σίγμα) is the eighteenth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 200. In general mathematics, uppercase Σ is used as ...
) receptors are no longer considered to be opioid receptors because their activation is not reversed by the opioid inverse-agonist naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
, they do not exhibit high-affinity binding for classical opioids, and they are stereoselective for dextro-rotatory isomers
In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers.
Iso ...
while the other opioid receptors are stereo-selective for levo-rotatory isomers. In addition, there are three subtypes of μ-receptor: μ1 and μ2, and the newly discovered μ3. Another receptor of clinical importance is the opioid-receptor-like receptor 1 (ORL1), which is involved in pain responses as well as having a major role in the development of tolerance to μ-opioid agonists used as analgesics. These are all G-protein coupled receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of protein family, evolution ...
s acting on GABAergic neurotransmission
Neurotransmission (Latin: ''transmissio'' "passage, crossing" from ''transmittere'' "send, let through") is the process by which signaling molecules called neurotransmitters are released by the axon terminal of a neuron (the presynaptic neuron), ...
.
The pharmacodynamic
Pharmacodynamics (PD) is the study of the biochemical and physiologic effects of drugs (especially pharmaceutical drugs). The effects can include those manifested within animals (including humans), microorganisms, or combinations of organisms (for ...
response to an opioid depends upon the receptor to which it binds, its affinity for that receptor, and whether the opioid is an agonist
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...
or an antagonist
An antagonist is a character in a story who is presented as the chief foe of the protagonist.
Etymology
The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...
. For example, the supraspinal analgesic properties of the opioid agonist morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
are mediated by activation of the μ1 receptor; respiratory depression and physical dependence
Physical dependence is a physical condition caused by chronic use of a tolerance-forming drug, in which abrupt or gradual drug withdrawal causes unpleasant physical symptoms. Physical dependence can develop from low-dose therapeutic use of certai ...
by the μ2 receptor; and sedation and spinal analgesia by the κ receptor. Each group of opioid receptors elicits a distinct set of neurological responses, with the receptor subtypes (such as μ1 and μ2 for example) providing even more easurablyspecific responses. Unique to each opioid is its distinct binding affinity to the various classes of opioid receptors (''e.g.'' the μ, κ, and δ opioid receptors are activated at different magnitudes according to the specific receptor binding affinities of the opioid). For example, the opiate alkaloid morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
exhibits high-affinity binding to the μ-opioid receptor, while ketazocine
Ketazocine (INN), also known as ketocyclazocine, is a benzomorphan derivative used in opioid receptor research. Ketazocine, for which the receptor is named, is an exogenous opioid that binds to the κ opioid receptor.
Activation of this receptor ...
exhibits high affinity to ĸ receptors. It is this combinatorial mechanism that allows for such a wide class of opioids and molecular designs to exist, each with its own unique effect profile. Their individual molecular structure is also responsible for their different duration of action, whereby metabolic breakdown (such as ''N''-dealkylation) is responsible for opioid metabolism.
Functional selectivity
A new strategy of drug development takes receptor signal transduction
Signal transduction is the process by which a chemical or physical signal is transmitted through a cell as a series of molecular events, most commonly protein phosphorylation catalyzed by protein kinases, which ultimately results in a cellula ...
into consideration. This strategy strives to increase the activation of desirable signalling pathways while reducing the impact on undesirable pathways. This differential strategy has been given several names, including functional selectivity
Functional selectivity (or “agonist trafficking”, “biased agonism”, “biased signaling”, "ligand bias" and “differential engagement”) is the ligand-dependent selectivity for certain signal transduction pathways relative to a referen ...
and biased agonism. The first opioid that was intentionally designed as a biased agonist and placed into clinical evaluation is the drug oliceridine
Oliceridine, sold under the brand name Olinvyk, is an opioid medication that is used for the treatment of moderate to severe acute pain in adults. It is given by intravenous (IV) injection.
The most common side effects include nausea, vomiting, ...
. It displays analgesic activity and reduced adverse effects.
Opioid comparison
Extensive research has been conducted to determine equivalence ratios comparing the relative potency of opioids. Given a dose of an opioid, an equianalgesic
An equianalgesic chart is a conversion chart that lists equivalent doses of analgesics (drugs used to relieve pain). Equianalgesic charts are used for calculation of an equivalent dose (a dose which would offer an equal amount of analgesia) betwee ...
table is used to find the equivalent dosage of another. Such tables are used in opioid rotation practices, and to describe an opioid by comparison to morphine, the reference opioid. Equianalgesic tables typically list drug half-lives, and sometimes equianalgesic doses of the same drug by means of administration, such as morphine: oral and intravenous.
Binding profiles
Usage
Opioid prescriptions in the US increased from 76 million in 1991 to 207 million in 2013.
In the 1990s, opioid prescribing increased significantly. Once used almost exclusively for the treatment of acute pain or pain due to cancer, opioids are now prescribed liberally for people experiencing chronic pain. This has been accompanied by rising rates of accidental addiction and accidental overdoses leading to death. According to the International Narcotics Control Board
The International Narcotics Control Board (INCB) is an independent treaty body, one of the four treaty-mandated bodies under international drug control law (alongside the Commission on Narcotic Drugs, UNODC on behalf of the Secretary-General, an ...
, the United States and Canada lead the per capita consumption of prescription opioids. The number of opioid prescriptions per capita in the United States and Canada is double the consumption in the European Union, Australia, and New Zealand. Certain populations have been affected by the opioid addiction crisis more than others, including First World
The concept of First World originated during the Cold War and comprised countries that were under the influence of the United States and the rest of NATO and opposed the Soviet Union and/or communism during the Cold War. Since the collapse of ...
communities and low-income populations. Public health specialists say that this may result from the unavailability or high cost of alternative methods for addressing chronic pain. Opioids have been described as a cost-effective treatment for chronic pain, but the impact of the opioid epidemic
The opioid epidemic, also referred to as the opioid crisis, is the rapid increase in the overuse, misuse/abuse, and overdose deaths attributed either in part or in whole to the class of drugs opiates/opioids since the 1990s. It includes the sign ...
and deaths caused by opioid overdoses should be considered in assessing their cost-effectiveness. Data from 2017 suggest that in the U.S. about 3.4 percent of the U.S. population are prescribed opioids for daily pain management. Calls for opioid deprescribing have led to broad scale opioid tapering
Opioid tapering is the reduction of opioid
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression o ...
practices with little scientific evidence to support the safety or benefit for patients with chronic pain.
History
Naturally occurring opioids
Opioids are among the world's oldest known drugs. The earliest known evidence of ''Papaver somniferum
''Papaver somniferum'', commonly known as the opium poppy or breadseed poppy, is a species of flowering plant in the family Papaveraceae. It is the species of plant from which both opium and poppy seeds are derived and is also a valuable orname ...
'' in a human archaeological site dates to the Neolithic
The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts ...
period around 5,700–5,500 BC. Its seeds have been found at Cueva de los Murciélagos
The Cueva de los Murciélagos is a cave system in the located about 4 km southeast of the town of Zuheros in the southern province of Córdoba in Spain. Although the caves were discovered in 1868, they were not studied until 1938. The cave ...
in the Iberian Peninsula
The Iberian Peninsula (),
**
* Aragonese and Occitan: ''Peninsula Iberica''
**
**
* french: Péninsule Ibérique
* mwl, Península Eibérica
* eu, Iberiar penintsula also known as Iberia, is a peninsula in southwestern Europe, defi ...
and La Marmotta in the Italian Peninsula.
Use of the opium poppy for medical, recreational, and religious purposes can be traced to the fourth century BC, when ideograms on Sumer
Sumer () is the earliest known civilization in the historical region of southern Mesopotamia (south-central Iraq), emerging during the Chalcolithic and early Bronze Ages between the sixth and fifth millennium BC. It is one of the cradles of c ...
ians clay tablets mention the use of "Hul Gil", a "plant of joy".
Opium was known to the Egyptians, and is mentioned in the Ebers Papyrus as an ingredient in a mixture for the soothing of children, and for the treatment of breast abscesses.
Opium was also known to the Greeks.
It was valued by Hippocrates
Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history of ...
( – ) and his students for its sleep-inducing properties, and used for the treatment of pain. The Latin saying "Sedare dolorem opus divinum est", trans. "Alleviating pain is the work of the divine", has been variously ascribed to Hippocrates and to Galen of Pergamum
Aelius Galenus or Claudius Galenus ( el, Κλαύδιος Γαληνός; September 129 – c. AD 216), often Anglicized as Galen () or Galen of Pergamon, was a Greek physician, surgeon and philosopher in the Roman Empire. Considered to be one of ...
. The medical use of opium is later discussed by Pedanius Dioscorides
Pedanius Dioscorides ( grc-gre, Πεδάνιος Διοσκουρίδης, ; 40–90 AD), “the father of pharmacognosy”, was a Greek physician, pharmacologist, botanist, and author of ''De materia medica'' (, On Medical Material) —a 5-vol ...
( – 90 AD), a Greek physician serving in the Roman army, in his five-volume work, ''De Materia Medica
(Latin name for the Greek work , , both meaning "On Medical Material") is a pharmacopoeia of medicinal plants and the medicines that can be obtained from them. The five-volume work was written between 50 and 70 CE by Pedanius Dioscorides, a ...
''.
During the Islamic Golden Age
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
, the use of opium was discussed in detail by Avicenna
Ibn Sina ( fa, ابن سینا; 980 – June 1037 CE), commonly known in the West as Avicenna (), was a Persian polymath who is regarded as one of the most significant physicians, astronomers, philosophers, and writers of the Islamic G ...
( – June 1037 AD) in ''The Canon of Medicine
''The Canon of Medicine'' ( ar, القانون في الطب, italic=yes ''al-Qānūn fī al-Ṭibb''; fa, قانون در طب, italic=yes, ''Qanun-e dâr Tâb'') is an encyclopedia of medicine in five books compiled by Persian physician-phi ...
''. The book's five volumes include information on opium's preparation, an array of physical effects, its use to treat a variety of illness, contraindications for its use, its potential danger as a poison and its potential for addiction. Avicenna discouraged opium's use except as a last resort, preferring to address the causes of pain rather than trying to minimize it with analgesics
An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It i ...
. Many of Avicenna's observations have been supported by modern medical research.
Exactly when the world became aware of opium in India and China is uncertain, but opium was mentioned in the Chinese medical work ''K'ai-pao-pen-tsdo'' (973 AD) By 1590 AD, opium poppies were a staple spring crop in the Subah
A Subah was the term for a province (State) in the Mughal Empire. The word is derived from Arabic and Persian. The governor/ruler of a ''Subah'' was known as a '' subahdar'' (sometimes also referred to as a "''Subeh''"), which later became ''subed ...
s of Agra
Agra (, ) is a city on the banks of the Yamuna river in the Indian state of Uttar Pradesh, about south-east of the national capital New Delhi and 330 km west of the state capital Lucknow. With a population of roughly 1.6 million, Agra is ...
region.
The physician Paracelsus
Paracelsus (; ; 1493 – 24 September 1541), born Theophrastus von Hohenheim (full name Philippus Aureolus Theophrastus Bombastus von Hohenheim), was a Swiss physician, alchemist, lay theologian, and philosopher of the German Renaissance.
He w ...
(–1541) is often credited with reintroducing opium into medical use in Western Europe
Western Europe is the western region of Europe. The region's countries and territories vary depending on context.
The concept of "the West" appeared in Europe in juxtaposition to "the East" and originally applied to the ancient Mediterranean ...
, during the German Renaissance
The German Renaissance, part of the Northern Renaissance, was a cultural and artistic movement that spread among Germany, German thinkers in the 15th and 16th centuries, which developed from the Italian Renaissance. Many areas of the arts and ...
. He extolled opium's benefits for medical use. He also claimed to have an "arcanum", a pill which he called laudanum
Laudanum is a tincture of opium containing approximately 10% powdered opium by weight (the equivalent of 1% morphine). Laudanum is prepared by dissolving extracts from the opium poppy (''Papaver somniferum Linnaeus'') in alcohol (ethanol).
Red ...
, that was superior to all others, particularly when death was to be cheated. ("Ich hab' ein Arcanum – heiss' ich Laudanum, ist über das Alles, wo es zum Tode reichen will.") Later writers have asserted that Paracelsus' recipe for laudanum contained opium, but its composition remains unknown.
Laudanum
The term laudanum was used generically for a useful medicine until the 17th century. After Thomas Sydenham
Thomas Sydenham (10 September 1624 – 29 December 1689) was an English physician. He was the author of ''Observationes Medicae'' which became a standard textbook of medicine for two centuries so that he became known as 'The English Hippocrate ...
introduced the first liquid tincture of opium, "laudanum" came to mean a mixture of both opium and alcohol.
Sydenham's 1669 recipe for laudanum mixed opium with wine, saffron, clove and cinnamon. Sydenham's laudanum was used widely in both Europe and the Americas until the 20th century.
Other popular medicines, based on opium, included Paregoric
Paregoric, or camphorated tincture of opium, also known as ''tinctura opii camphorata'', is a traditional patent medicine known for its antidiarrheal, antitussive, and analgesic properties.
According to Goodman and Gilman's 1965 edition, "Par ...
, a much milder liquid preparation for children; Black-drop, a stronger preparation; and Dover's powder
Dover's powder was a traditional medicine against cold and fever developed by Thomas Dover. It is no longer in use in modern medicine, but may have been in use at least through the 1960s.
A 1958 source describes Dover's Powder as follows:
"Powder ...
.
The opium trade
Opium became a major colonial commodity, moving legally and illegally through trade networks involving India, the Portuguese, the Dutch, the British and China, among others.
The British East India Company
The East India Company (EIC) was an English, and later British, joint-stock company founded in 1600 and dissolved in 1874. It was formed to trade in the Indian Ocean region, initially with the East Indies (the Indian subcontinent and Southea ...
saw the opium trade as an investment opportunity in 1683 AD. In 1773 the Governor of Bengal established a monopoly on the production of Bengal opium, on behalf of the East India Company. The cultivation and manufacture of Indian opium was further centralized and controlled through a series of acts, between 1797 and 1949. The British balanced an economic deficit from the importation of Chinese tea
Tea is a beverage made from the leaves of tea plants ('' Camellia sinensis'') and boiled water. Tea leaves are processed using traditional Chinese methods. Chinese tea is consumed throughout the day, including during meals, as a substitute for ...
by selling Indian opium which was smuggled into China in defiance of Chinese government
The Government of the People's Republic of China () is an authoritarian political system in the People's Republic of China under the exclusive political leadership of the Chinese Communist Party (CCP). It consists of legislative, executive, mili ...
bans. This led to the First
First or 1st is the ordinal form of the number one (#1).
First or 1st may also refer to:
*World record, specifically the first instance of a particular achievement
Arts and media Music
* 1$T, American rapper, singer-songwriter, DJ, and rec ...
(1839–1842) and Second Opium War
The Second Opium War (), also known as the Second Anglo-Sino War, the Second China War, the Arrow War, or the Anglo-French expedition to China, was a colonial war lasting from 1856 to 1860, which pitted the British Empire and the French Emp ...
s (1856–1860) between China and Britain.
Morphine
In the 19th century, two major scientific advances were made that had far-reaching effects. Around 1804, German pharmacist Friedrich Sertürner
Friedrich Wilhelm Adam Sertürner (19 June 1783 – 20 February 1841) was a German pharmacist and a pioneer of alkaloid chemistry. He is best known for his discovery of morphine in 1804.
Biography
Friedrich Wilhelm Adam Sertürner was born to J ...
isolated morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
from opium. He described its crystallization, structure, and pharmacological properties in a well-received paper in 1817.
Morphine was the first alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...
to be isolated from any medicinal plant, the beginning of modern scientific drug discovery.
The second advance, nearly fifty years later, was the refinement of the hypodermic needle
A hypodermic needle (from Greek ὑπο- (''hypo-'' = under), and δέρμα (''derma'' = skin)), one of a category of medical tools which enter the skin, called sharps, is a very thin, hollow tube with one sharp tip. It is commonly used w ...
by Alexander Wood and others. Development of a glass syringe with a subcutaneous needle made it possible to easily administer controlled measurable doses of a primary active compound.
Morphine was initially hailed as a wonder drug for its ability to ease pain. It could help people sleep, and had other useful side effects, including control of coughing
A cough is a sudden expulsion of air through the large breathing passages that can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three phas ...
and diarrhea
Diarrhea, also spelled diarrhoea, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin wi ...
. It was widely prescribed by doctors, and dispensed without restriction by pharmacists. During the American Civil War
The American Civil War (April 12, 1861 – May 26, 1865; also known by other names) was a civil war in the United States. It was fought between the Union ("the North") and the Confederacy ("the South"), the latter formed by states th ...
, opium and laudanum were used extensively to treat soldiers. It was also prescribed frequently for women, for menstrual pain
Dysmenorrhea, also known as period pain, painful periods or menstrual cramps, is pain during menstruation. Its usual onset occurs around the time that menstruation begins. Symptoms typically last less than three days. The pain is usually in the ...
and diseases of a "nervous character".
At first it was assumed (wrongly) that this new method of application would not be addictive.
Codeine
Codeine
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...
was discovered in 1832 by Pierre Jean Robiquet
Pierre Jean Robiquet (13 January 1780 – 29 April 1840) was a French chemist. He laid founding work in identifying amino acids, the fundamental building blocks of proteins. He did this through recognizing the first of them, asparagine, in 1806 ...
. Robiquet was reviewing a method for morphine extraction, described by Scottish chemist William Gregory (1803–1858). Processing the residue left from Gregory's procedure, Robiquet isolated a crystalline substance from the other active components of opium. He wrote of his discovery: "Here is a new substance found in opium ... We know that morphine, which so far has been thought to be the only active principle of opium, does not account for all the effects and for a long time the physiologists are claiming that there is a gap that has to be filled." His discovery of the alkaloid led to the development of a generation of antitussive and antidiarrheal medicines based on codeine.
Semisynthetic and synthetic opioids
Synthetic opioids were invented, and biological mechanisms for their actions discovered, in the 20th century. Scientists have searched for non-addictive forms of opioids, but have created stronger ones instead. In England Charles Romley Alder Wright
Charles Romley Alder Wright FCS, FRS (7 September 1844 – 25 June 1894) was an English lecturer in chemistry and physics at St Mary's Hospital Medical School in London, England. He was a founder of the Royal Institute of Chemistry.
Alder ...
developed hundreds of opiate compounds in his search for a nonaddictive opium derivative. In 1874 he became the first person to synthesize diamorphine
Heroin, also known as diacetylmorphine and diamorphine among other names, is a potent opioid mainly used as a recreational drug for its euphoric effects. Medical grade diamorphine is used as a pure hydrochloride salt. Various white and brown ...
(heroin), using a process called acetylation
:
In organic chemistry, acetylation is an organic esterification reaction with acetic acid. It introduces an acetyl group into a chemical compound. Such compounds are termed ''acetate esters'' or simply '' acetates''. Deacetylation is the oppo ...
which involved boiling morphine with acetic anhydride
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH3CO)2O. Commonly abbreviated Ac2O, it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis. It is a col ...
for several hours.
Heroin received little attention until it was independently synthesized by Felix Hoffmann
Felix Hoffmann (21 January 1868 – 8 February 1946) was a German chemist notable for re-synthesising diamorphine (independently from C.R. Alder Wright who synthesized it 23 years earlier), which was popularized under the Bayer trade name ...
(1868–1946), working for Heinrich Dreser
Heinrich Dreser (1 October 1860 – 21 December 1924) was a German chemist responsible for the aspirin and heroin projects at Bayer AG. He was also a key figure in creating the widely used modern drug codeine. Dreser was born in Darmstadt.
...
(1860–1924) at Bayer
Bayer AG (, commonly pronounced ; ) is a German multinational corporation, multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of busi ...
Laboratories. Dreser brought the new drug to market as an analgesic
An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...
and a cough treatment for tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...
, bronchitis
Bronchitis is inflammation of the bronchi (large and medium-sized airways) in the lungs that causes coughing. Bronchitis usually begins as an infection in the nose, ears, throat, or sinuses. The infection then makes its way down to the bronchi. ...
, and asthma
Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, cou ...
in 1898. Bayer ceased production in 1913, after heroin's addictive potential was recognized.
Several semi-synthetic opioids were developed in Germany in the 1910s. The first, oxymorphone
Oxymorphone (sold under the brand names Numorphan and Opana among others) is a highly potent opioid analgesic indicated for treatment of severe pain. Pain relief after injection begins after about 5–10 minutes, after oral administration it beg ...
, was synthesized from thebaine
Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, '' Thēbai'' (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically similar ...
, an opioid alkaloid in opium poppies, in 1914.
Next, Martin Freund and Edmund Speyer developed oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
, also from thebaine, at the University of Frankfurt in 1916.
In 1920, hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
was prepared by Carl Mannich
Carl Ulrich Franz Mannich (8 March 1877 in Breslau – 5 March 1947 in Karlsruhe) was a German chemist. From 1927 to 1943 he was professor for pharmaceutical chemistry at the University of Berlin. His areas of expertise were keto bases, alcoh ...
and Helene Löwenheim, deriving it from codeine. In 1924, hydromorphone
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...
was synthesized by adding hydrogen to morphine. Etorphine
Etorphine (M99) is a semi-synthetic opioid possessing an analgesic potency approximately 1,000–3,000 times that of morphine. It was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather the r ...
was synthesized in 1960, from the oripavine
Oripavine is an opioid and the major metabolite of thebaine. It is the parent compound from which a series of semi-synthetic opioids are derived, which includes the compounds etorphine and buprenorphine. Although its analgesic potency is compar ...
in opium poppy straw. Buprenorphine
Buprenorphine is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection (intravenous and subcutaneous), as a skin patch (transdermal), ...
was discovered in 1972.
The first fully synthetic opioid was meperidine
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a synthetic opioid analgesic, pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemis ...
(later demerol), found serendipitously by German chemist Otto Eisleb (or Eislib) at IG Farben
Interessengemeinschaft Farbenindustrie AG (), commonly known as IG Farben (German for 'IG Dyestuffs'), was a German chemical and pharmaceutical conglomerate (company), conglomerate. Formed in 1925 from a merger of six chemical companies—BASF, ...
in 1932. Meperidine was the first opiate to have a structure unrelated to morphine, but with opiate-like properties. Its analgesic effects were discovered by Otto Schaumann in 1939.
Gustav Ehrhart
Gustav Ehrhart (21 December 1894 – 11 December 1971) was a Germans, German chemist. He synthesized the first fully synthetic opioid analgesic, methadone, together with Max Bockmühl.
Education and professional positions
Ehrhart studied chemi ...
and Max Bockmühl
Max Bockmühl (2 September 1882 – 5 January 1949) was a German inventor and chemist.
Life
Bockmühl studied chemistry and pharmacy. He worked as chemist in Germany. Together with Gustav Ehrhart working for I.G. Farbenindustrie AG at the ...
, also at IG Farben,
built on the work of Eisleb and Schaumann. They developed "Hoechst 10820" (later methadone
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...
) around 1937.
In 1959 the Belgian physician Paul Janssen
Paul Adriaan Jan, Baron Janssen (12 September 1926 - 11 November 2003) was a Belgian physician. He was the founder of Janssen Pharmaceutica, a pharmaceutical company with over 20,000 employees which is now a subsidiary of Johnson & Johnson.
Ea ...
developed fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
, a synthetic drug with 30 to 50 times the potency of heroin.
Nearly 150 synthetic opioids are now known.
Criminalization and medical use
Non-clinical use of opium was criminalized in the United States by the Harrison Narcotics Tax Act
The Harrison Narcotics Tax Act (Ch. 1, ) was a United States federal law that regulated and taxed the production, importation, and distribution of opiates and coca products. The act was proposed by United States Representative, Representative Fra ...
of 1914, and by many other laws. The use of opioids was stigmatized, and it was seen as a dangerous substance, to be prescribed only as a last resort for dying patients. The Controlled Substances Act
The Controlled Substances Act (CSA) is the statute establishing federal government of the United States, federal drug policy of the United States, U.S. drug policy under which the manufacture, importation, possession, use, and distribution of ...
of 1970 eventually relaxed the harshness of the Harrison Act.
In the United Kingdom the 1926 report of the Departmental Committee on Morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
and Heroin Addiction
Addiction is a neuropsychological disorder characterized by a persistent and intense urge to engage in certain behaviors, one of which is the usage of a drug, despite substantial harm and other negative consequences. Repetitive drug use o ...
under the Chairmanship of the President of the Royal College of Physicians reasserted medical control and established the "British system" of control—which lasted until the 1960s.
In the 1980s the World Health Organization published guidelines for prescribing drugs, including opioids, for different levels of pain. In the U.S., Kathleen Foley and Russell Portenoy became leading advocates for the liberal use of opioids as painkillers for cases of "intractable non-malignant pain".
With little or no scientific evidence to support their claims, industry scientists and advocates suggested that people with chronic pain would be resistant to addiction.
The release of OxyContin
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
in 1996 was accompanied by an aggressive marketing campaign promoting the use of opioids for pain relief. Increasing prescription of opioids fueled a growing black market for heroin. Between 2000 and 2014 there was an "alarming increase in heroin use across the country and an epidemic of drug overdose deaths".
As a result, health care organizations and public health groups, such as Physicians for Responsible Opioid Prescribing, have called for decreases in the prescription of opioids. In 2016, the Centers for Disease Control and Prevention (CDC) issued a new set of guidelines for the prescription of opioids "for chronic pain outside of active cancer treatment, palliative care, and end-of-life care" and the increase of opioid tapering
Opioid tapering is the reduction of opioid
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression o ...
.
"Remove the Risk"
In April 2019 the U.S. Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...
announced the launch of a new education campaign to help Americans understand the important role they play in removing and properly disposing of unused prescription opioids from their homes. This new initiative is part of the FDA's continued efforts to address the nationwide opioid crisis
The opioid epidemic, also referred to as the opioid crisis, is the rapid increase in the overuse, misuse/abuse, and overdose deaths attributed either in part or in whole to the class of drugs opiates/opioids since the 1990s. It includes the sign ...
(see below) and aims to help decrease unnecessary exposure to opioids and prevent new addiction. Th
"Remove the Risk" campaign
is targeting women ages 35–64, who are most likely to oversee household health care decisions and often serve as the gatekeepers to opioids and other prescription medications in the home.
Society and culture
Definition
The term "opioid" originated in the 1950s. It combines "opium" + "-oid" meaning "opiate-like" ("opiates" being morphine and similar drugs derived from opium
Opium (or poppy tears, scientific name: ''Lachryma papaveris'') is dried latex obtained from the seed capsules of the opium poppy ''Papaver somniferum''. Approximately 12 percent of opium is made up of the analgesic alkaloid morphine, which i ...
). The first scientific publication to use it, in 1963, included a footnote stating, "In this paper, the term, 'opioid', is used in the sense originally proposed by George H. Acheson (personal communication) to refer to any chemical compound with morphine-like activities". By the late 1960s, research found that opiate effects are mediated by activation of specific molecular receptors in the nervous system, which were termed "opioid receptors". The definition of "opioid" was later refined to refer to substances that have morphine-like activities that are mediated by the activation of opioid receptors. One modern pharmacology textbook states: "the term opioid applies to all agonists and antagonists with morphine-like activity, and also the naturally occurring and synthetic opioid peptides". Another pharmacology reference eliminates the ''morphine-like'' requirement: "Opioid, a more modern term, is used to designate all substances, both natural and synthetic, that bind to opioid receptors (including antagonists)". Some sources define the term ''opioid'' to exclude ''opiates'', and others use ''opiate'' comprehensively instead of ''opioid'', but ''opioid'' used inclusively is considered modern, preferred and is in wide use.
Efforts to reduce recreational use in the US
In 2011, the Obama administration released a white paper describing the administration's plan to deal with the opioid crisis
The opioid epidemic, also referred to as the opioid crisis, is the rapid increase in the overuse, misuse/abuse, and overdose deaths attributed either in part or in whole to the class of drugs opiates/opioids since the 1990s. It includes the sign ...
. The administration's concerns about addiction and accidental overdosing have been echoed by numerous other medical and government advisory groups around the world.
As of 2015, prescription drug monitoring programs exist in every state, except for Missouri. These programs allow pharmacists and prescribers to access patients' prescription histories in order to identify suspicious use. However, a survey of US physicians published in 2015 found that only 53% of doctors used these programs, while 22% were not aware that the programs were available to them. The Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...
was tasked with establishing and publishing a new guideline, and was heavily lobbied. In 2016, the United States Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...
published its Guideline for Prescribing Opioids for Chronic Pain, recommending that opioids only be used when benefits for pain and function are expected to outweigh risks, and then used at the lowest effective dosage, with avoidance of concurrent opioid and benzodiazepine use whenever possible. Research suggests that the prescription of high doses of opioids related to chronic opioid therapy
Chronic may refer to:
* Chronic (cannabis), a slang name for high quality marijuana
* Chronic condition, a condition or disease that is persistent or otherwise long-lasting in its effects
* Chronic toxicity, a substance with toxic effects after c ...
(COT) can at times be prevented through state legislative guidelines and efforts by health plans that devote resources and establish shared expectations for reducing higher doses.
On 10 August 2017, Donald Trump
Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who served as the 45th president of the United States from 2017 to 2021.
Trump graduated from the Wharton School of the University of Pe ...
declared the opioid crisis a (non-FEMA) national public health emergency.
Global shortages
Morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
and other poppy-based medicines have been identified by the World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
as essential in the treatment of severe pain. As of 2002, seven countries (USA, UK, Italy, Australia, France, Spain and Japan) use 77% of the world's morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
supplies, leaving many emerging countries lacking in pain relief medication. The current system of supply of raw poppy materials to make poppy-based medicines is regulated by the International Narcotics Control Board
The International Narcotics Control Board (INCB) is an independent treaty body, one of the four treaty-mandated bodies under international drug control law (alongside the Commission on Narcotic Drugs, UNODC on behalf of the Secretary-General, an ...
under the provision of the 1961 Single Convention on Narcotic Drugs
The Single Convention on Narcotic Drugs, 1961 (Single Convention, 1961 Convention, or C61) is an international treaty that controls activities (cultivation, production, supply, trade, transport) of specific narcotic drugs and lays down a syst ...
. The amount of raw poppy materials that each country can demand annually based on these provisions must correspond to an estimate of the country's needs taken from the national consumption within the preceding two years. In many countries, underprescription of morphine is rampant because of the high prices and the lack of training in the prescription of poppy-based drugs. The World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
is now working with administrations from various countries to train healthworkers and to develop national regulations regarding drug prescription to facilitate a greater prescription of poppy-based medicines.
Another idea to increase morphine availability is proposed by the Senlis Council
The International Council on Security and Development (ICOS) is an international think tank that focuses on Afghanistan and other conflict zones such as Iraq and Somalia. ICOS is a project of the Network of European Foundations for Innovative Co ...
, who suggest, through their proposal for Afghan Morphine, that Afghanistan
Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
could provide cheap pain relief solutions to emerging countries as part of a second-tier system of supply that would complement the current INCB
The International Narcotics Control Board (INCB) is an independent treaty body, one of the four treaty-mandated bodies under international drug control law (alongside the Commission on Narcotic Drugs, UNODC on behalf of the Secretary-General, an ...
regulated system by maintaining the balance and closed system that it establishes while providing finished product morphine to those in severe pain and unable to access poppy-based drugs under the current system.
Recreational use
Opioids can produce strong feelings of euphoria
Euphoria ( ) is the experience (or affect) of pleasure or excitement and intense feelings of well-being and happiness. Certain natural rewards and social activities, such as aerobic exercise, laughter, listening to or making music and da ...
and are frequently used recreationally. Traditionally associated with illicit opioids such as heroin, prescription opioids are misused recreationally.
Drug misuse
Substance abuse, also known as drug abuse, is the use of a drug in amounts or by methods which are harmful to the individual or others. It is a form of substance-related disorder. Differing definitions of drug abuse are used in public health, ...
and non-medical use include the use of drugs for reasons or at doses other than prescribed. Opioid misuse can also include providing medications to persons for whom it was not prescribed. Such diversion may be treated as crimes, punishable by imprisonment in many countries. In 2014, almost 2 million Americans abused or were dependent on prescription opioids.
Classification
There are a number of broad classes of opioids:
* Natural opiates
An opiate, in classical pharmacology, is a substance derived from opium. In more modern usage, the term ''opioid'' is used to designate all substances, both natural and synthetic, that bind to opioid receptors in the brain (including antagonist ...
: alkaloids
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar st ...
contained in the resin of the opium poppy
''Papaver somniferum'', commonly known as the opium poppy or breadseed poppy, is a species of flowering plant in the family Papaveraceae. It is the species of plant from which both opium and poppy seeds are derived and is also a valuable ornamen ...
, primarily morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
, codeine
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...
, and thebaine
Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, '' Thēbai'' (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically similar ...
, but not papaverine
Papaverine (Latin ''papaver'', "poppy") is an opium alkaloid antispasmodic drug, used primarily in the treatment of visceral spasms and vasospasms (especially those involving the intestines, heart, or brain), occasionally in the treatment of erec ...
and noscapine
Noscapine (also known as Narcotine, Nectodon, Nospen, Anarcotine and (archaic) Opiane) is a benzylisoquinoline alkaloid, of the phthalideisoquinoline structural subgroup, which has been isolated from numerous species of the family Papaveraceae ( ...
which have a different mechanism of action; The following could be considered natural opiates: The leaves from Mitragyna speciosa
''Mitragyna speciosa'' (commonly known as kratom, an herbal leaf from a tree of the Rubiaceae family, ) is a tropical evergreen tree in the coffee family native to Southeast Asia. It is indigenous to Thailand, Indonesia, Malaysia, Myanmar, and ...
(also known as kratom
''Mitragyna speciosa'' (commonly known as kratom, an herbal leaf from a tree of the Rubiaceae family, ) is a tropical evergreen tree in the coffee family native to Southeast Asia. It is indigenous to Thailand, Indonesia, Malaysia, Myanmar, and ...
) contain a few naturally-occurring opioids, active via Mu- and Delta receptors. Salvinorin A
Salvinorin A is the main active psychotropic molecule in '' Salvia divinorum''. Salvinorin A is considered a dissociative hallucinogen.
It is structurally distinct from other naturally occurring hallucinogens (such as DMT, psilocybin, and ...
, found naturally in the Salvia divinorum
''Salvia divinorum'' (Latin: "sage of the diviners"; also called ska maría pastora, seer's sage, yerba de la pastora, magic mint or simply salvia) is a plant species with transient psychoactive properties when its leaves are consumed by che ...
plant, is a kappa-opioid receptor agonist.
* Esters of morphine opiates: slightly chemically altered but more natural than the semi-synthetics, as most are morphine prodrugs, diacetylmorphine
Heroin, also known as diacetylmorphine and diamorphine among other names, is a potent opioid mainly used as a recreational drug for its euphoric effects. Medical grade diamorphine is used as a pure hydrochloride salt. Various white and brown ...
(morphine diacetate; heroin), nicomorphine
Nicomorphine (Vilan, Subellan, Gevilan, MorZet) is the 3,6-dinicotinate ester of morphine. It is a strong opioid agonist analgesic two to three times as potent as morphine with a side effect profile similar to that of dihydromorphine, morphine, an ...
(morphine dinicotinate), dipropanoylmorphine
Dipropanoylmorphine (Dipropionylmorphine in U.S. English) is an opiate derivative, the 3,6-dipropanoyl ester of morphine. It was developed in 1972 as an analgesic. It is rarely used in some countries for the relief of severe pain such as that cause ...
(morphine dipropionate), desomorphine
Desomorphine is a semi-synthetic opioid commercialized by Roche, with powerful, fast-acting effects, such as sedation and analgesia. It was first discovered and patented by a German team working for Knoll in 1920 but was not generally recognized ...
, acetylpropionylmorphine
Acetylpropionylmorphine is an opiate analogue that is an ester of morphine. It was developed in the early 1900s after first being synthesised in Great Britain in 1875 but shelved along with heroin and various other esters of morphine. Acetylpropi ...
, dibenzoylmorphine
Dibenzoylmorphine is an opiate analogue that is a derivative of morphine. It was developed in the early 1900s after first having been synthesised in 1875 in the UK by the CR Alders Wright organisation at Bayer, along with various other esters of ...
, diacetyldihydromorphine
Diacetyldihydromorphine (also known as Paralaudin, dihydroheroin, acetylmorphinol) is a potent opiate derivative developed in Germany in 1928 which is rarely used in some countries for the treatment of severe pain such as that caused by terminal c ...
;
* Semi-synthetic opioids: created from either the natural opiates or morphine esters, such as hydromorphone
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...
, hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
, oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
, oxymorphone
Oxymorphone (sold under the brand names Numorphan and Opana among others) is a highly potent opioid analgesic indicated for treatment of severe pain. Pain relief after injection begins after about 5–10 minutes, after oral administration it beg ...
, ethylmorphine
Ethylmorphine (also known as codethyline, dionine, and ethyl morphine) is an opioid analgesic and antitussive.
Side effects
Adverse effects are similar to other opioids and include drowsiness, constipation, vertigo, nausea, vomiting, and respirat ...
and buprenorphine
Buprenorphine is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection (intravenous and subcutaneous), as a skin patch (transdermal), ...
;
* Fully synthetic opioids: such as fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
, pethidine
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a synthetic opioid analgesic, pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemis ...
, levorphanol
Levorphanol (brand name Levo-Dromoran) is an opioid medication used to treat moderate to severe pain. It is the levorotatory enantiomer of the compound racemorphan. Its dextrorotatory counterpart is dextrorphan.
It was first described in German ...
, methadone
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...
, tramadol
Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an h ...
, tapentadol
Tapentadol, brand names Nucynta among others, is a centrally acting opioid analgesic of the benzenoid class with a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI). Analgesia occurs wit ...
, and dextropropoxyphene
Dextropropoxyphene is an analgesic in the opioid category, patented in 1955 and manufactured by Eli Lilly and Company. It is an optical isomer of levopropoxyphene. It is intended to treat mild pain and also has antitussive (cough suppressant) a ...
;
* Endogenous
Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell.
In contrast, exogenous substances and processes are those that originate from outside of an organism.
For example, es ...
opioid peptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides.
A ...
s, produced naturally in the body, such as endorphin
Endorphins (contracted from endogenous morphine) are chemical signals in the brain that block the perception of pain and increase feelings of wellbeing. They are produced and stored in an area of the brain known as the pituitary gland.
Hist ...
s, enkephalin
An enkephalin is a pentapeptide involved in regulating nociception in the body. The enkephalins are termed endogenous ligands, as they are internally derived and bind to the body's opioid receptors. Discovered in 1975, two forms of enkephalin ...
s, dynorphin
Dynorphins (Dyn) are a class of opioid peptides that arise from the precursor protein prodynorphin. When prodynorphin is cleaved during processing by proprotein convertase 2 (PC2), multiple active peptides are released: dynorphin A, dynorphin B, a ...
s, and endomorphin
Endomorphins are considered to be natural opioid neurotransmitters central to pain relief. The two known endomorphins, endomorphin-1 and endomorphin-2, are tetrapeptides, consisting of Tyr-Pro-Trp-Phe and Tyr-Pro-Phe-Phe amino acid sequences resp ...
s. Morphine, and some other opioids, which are produced in small amounts in the body, are included in this category.
Tramadol
Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an h ...
and tapentadol
Tapentadol, brand names Nucynta among others, is a centrally acting opioid analgesic of the benzenoid class with a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI). Analgesia occurs wit ...
, which act as monoamine uptake inhibitors also act as mild and potent agonist
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...
s (respectively) of the μ-opioid receptor
The μ-opioid receptors (MOR) are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins. They are also referred to as μ(''mu'')-opioid peptide (MOP) receptors. The prototypical ...
. Both drugs produce analgesia
Pain management is an aspect of medicine and health care involving relief of pain (pain relief, analgesia, pain control) in various dimensions, from acute and simple to chronic and challenging. Most physicians and other health professionals ...
even when naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
, an opioid antagonist, is administered.
Some minor opium alkaloids
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar st ...
and various substances with opioid action are also found elsewhere, including molecules present in kratom
''Mitragyna speciosa'' (commonly known as kratom, an herbal leaf from a tree of the Rubiaceae family, ) is a tropical evergreen tree in the coffee family native to Southeast Asia. It is indigenous to Thailand, Indonesia, Malaysia, Myanmar, and ...
, ''Corydalis
''Corydalis'' (from Greek ''korydalís'' "crested lark") is a genus of about 470 species of annual and perennial herbaceous plants in the family Papaveraceae, native to the temperate Northern Hemisphere and the high mountains of tropical eastern ...
'', and ''Salvia divinorum
''Salvia divinorum'' (Latin: "sage of the diviners"; also called ska maría pastora, seer's sage, yerba de la pastora, magic mint or simply salvia) is a plant species with transient psychoactive properties when its leaves are consumed by che ...
'' plants and some species of poppy aside from ''Papaver somniferum''. There are also strains which produce copious amounts of thebaine, an important raw material for making many semi-synthetic and synthetic opioids. Of all of the more than 120 poppy species, only two produce morphine.
Amongst analgesics there are a small number of agents which act on the central nervous system but not on the opioid receptor system and therefore have none of the other (narcotic) qualities of opioids although they may produce euphoria by relieving pain—a euphoria that, because of the way it is produced, does not form the basis of habituation, physical dependence, or addiction. Foremost amongst these are nefopam
Nefopam, sold under the brand name Acupan among others, is a centrally acting, non-opioid painkilling medication, that is primarily used to treat moderate to severe pain.
Nefopam acts in the brain and spinal cord to relieve pain via novel mecha ...
, orphenadrine
Orphenadrine (sold under many brand names) is an anticholinergic drug of the ethanolamine antihistamine class; it is closely related to diphenhydramine. It is a muscle relaxant that is used to treat muscle pain and to help with motor control in Pa ...
, and perhaps phenyltoloxamine
Phenyltoloxamine is an antihistamine with sedative and analgesic effects. It is available in combination with other drugs such as paracetamol (acetominophen).
Common use
Phenyltoloxamine is widely used in preparations as an enhancing agent f ...
or some other antihistamines
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ...
. Tricyclic antidepressant
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...
s have painkilling effect as well, but they're thought to do so by indirectly activating the endogenous opioid system. Paracetamol is predominantly a centrally acting analgesic (non-narcotic) which mediates its effect by action on descending serotoninergic (5-hydroxy triptaminergic) pathways, to increase 5-HT release (which inhibits release of pain mediators). It also decreases cyclo-oxygenase activity. It has recently been discovered that most or all of the therapeutic efficacy of paracetamol is due to a metabolite, AM404
AM404, also known as ''N''-arachidonoylaminophenol, is an active metabolite of paracetamol (acetaminophen), responsible for all or part of its analgesic action and anticonvulsant effects. Chemically, it is the amide formed from 4-aminophenol and ...
, which enhances the release of serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
and inhibits the uptake of anandamide
Anandamide (ANA), also known as ''N''-arachidonoylethanolamine (AEA), is a fatty acid neurotransmitter. Anandamide was the first endocannabinoid to be discovered: it participates in the body's endocannabinoid system by binding to cannabinoid rec ...
.
Other analgesics work peripherally (''i.e.'', not on the brain or spinal cord). Research is starting to show that morphine and related drugs may indeed have peripheral effects as well, such as morphine gel working on burns. Recent investigations discovered opioid receptors on peripheral sensory neurons. A significant fraction (up to 60%) of opioid analgesia can be mediated by such peripheral opioid receptors, particularly in inflammatory conditions such as arthritis, traumatic or surgical pain. Inflammatory pain is also blunted by endogenous opioid peptides activating peripheral opioid receptors.
It was discovered in 1953, that humans and some animals naturally produce minute amounts of morphine, codeine, and possibly some of their simpler derivatives like heroin and dihydromorphine
Dihydromorphine (Paramorfan, Paramorphan) is a semi-synthetic opioid structurally related to and derived from morphine. The 7,8-double bond in morphine is reduced to a single bond to get dihydromorphine.Rama Rao Nadendla. Principles Of Organic ...
, in addition to endogenous opioid peptides. Some bacteria are capable of producing some semi-synthetic opioids such as hydromorphone
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...
and hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
when living in a solution containing morphine or codeine respectively.
Many of the alkaloids
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar st ...
and other derivatives of the opium poppy are not opioids or narcotics; the best example is the smooth-muscle relaxant papaverine
Papaverine (Latin ''papaver'', "poppy") is an opium alkaloid antispasmodic drug, used primarily in the treatment of visceral spasms and vasospasms (especially those involving the intestines, heart, or brain), occasionally in the treatment of erec ...
. Noscapine is a marginal case as it does have CNS effects but not necessarily similar to morphine, and it is probably in a category all its own.
Dextromethorphan
Dextromethorphan (DXM) is a medication most often used as a cough suppressant in over-the-counter cold and cough medicines. It is sold in syrup, tablet, spray, and lozenge forms. In 2022, the FDA approved a formulation of it combined with bu ...
(the stereoisomer of levomethorphan
Levomethorphan (LVM) ( INN, BAN) is an opioid analgesic of the morphinan family that has never been marketed. It is the L-stereoisomer of racemethorphan (methorphan). The effects of the two isomers of the racemethorphan are quite different, with ...
, a semi-synthetic opioid agonist) and its metabolite dextrorphan
Dextrorphan (DXO) is a psychoactive drug of the morphinan class which acts as an antitussive or cough suppressant and dissociative hallucinogen. It is the dextrorotatory enantiomer of racemorphan; the levorotatory enantiomer is levorphanol. Dext ...
have no opioid analgesic effect at all despite their structural similarity to other opioids; instead they are potent NMDA antagonists
NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the ''N''-Methyl-D-aspartate receptor ( NMDAR). They are commonly used as anesthetics for animals and humans; the state of anesthesia they induc ...
and sigma 1 and 2-receptor agonists and are used in many over-the-counter
Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs, which may be supplied only to consumers possessing a valid prescr ...
cough suppressants.
Salvinorin A
Salvinorin A is the main active psychotropic molecule in '' Salvia divinorum''. Salvinorin A is considered a dissociative hallucinogen.
It is structurally distinct from other naturally occurring hallucinogens (such as DMT, psilocybin, and ...
is a unique selective, powerful ĸ-opioid receptor agonist. It is not properly considered an opioid nevertheless, because:
# chemically, it is not an alkaloid; and
# it has no typical opioid properties: absolutely no anxiolytic or cough-suppressant effects. It is instead a powerful hallucinogen
Hallucinogens are a large, diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Most hallucinogens can be categorized ...
.
Endogenous opioids
Opioid-peptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides.
A ...
s that are produced in the body include:
* Endorphin
Endorphins (contracted from endogenous morphine) are chemical signals in the brain that block the perception of pain and increase feelings of wellbeing. They are produced and stored in an area of the brain known as the pituitary gland.
Hist ...
s
* Enkephalin
An enkephalin is a pentapeptide involved in regulating nociception in the body. The enkephalins are termed endogenous ligands, as they are internally derived and bind to the body's opioid receptors. Discovered in 1975, two forms of enkephalin ...
s
* Dynorphin
Dynorphins (Dyn) are a class of opioid peptides that arise from the precursor protein prodynorphin. When prodynorphin is cleaved during processing by proprotein convertase 2 (PC2), multiple active peptides are released: dynorphin A, dynorphin B, a ...
s
* Endomorphin
Endomorphins are considered to be natural opioid neurotransmitters central to pain relief. The two known endomorphins, endomorphin-1 and endomorphin-2, are tetrapeptides, consisting of Tyr-Pro-Trp-Phe and Tyr-Pro-Phe-Phe amino acid sequences resp ...
s
β-endorphin
''beta''-Endorphin (β-endorphin) is an endogenous opioid neuropeptide and peptide hormone that is produced in certain neurons within the central nervous system and peripheral nervous system. It is one of three endorphins that are produced in ...
is expressed in Pro-opiomelanocortin
Pro-opiomelanocortin (POMC) is a precursor polypeptide with 241 amino acid residues. POMC is synthesized in corticotrophs of the anterior pituitary from the 267-amino-acid-long polypeptide precursor pre-pro-opiomelanocortin (pre-POMC), by the r ...
(POMC) cells in the arcuate nucleus
The arcuate nucleus of the hypothalamus (also known as ARH, ARC, or infundibular nucleus) is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. The arcuate nucleus includes several ...
, in the brainstem
The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is cont ...
and in immune cells, and acts through μ-opioid receptor
The μ-opioid receptors (MOR) are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins. They are also referred to as μ(''mu'')-opioid peptide (MOP) receptors. The prototypical ...
s. β-endorphin has many effects, including on sexual behavior
Human sexual activity, human sexual practice or human sexual behaviour is the manner in which humans experience and express their sexuality. People engage in a variety of sexual acts, ranging from activities done alone (e.g., masturbation) ...
and appetite
Appetite is the desire to eat food items, usually due to hunger. Appealing foods can stimulate appetite even when hunger is absent, although appetite can be greatly reduced by satiety. Appetite exists in all higher life-forms, and serves to regu ...
. β-endorphin is also secreted into the circulation from pituitary corticotropes
Corticotropes (or corticotrophs) are basophilic cells in the anterior pituitary that produce pro-opiomelanocortin (POMC) which undergoes cleavage to adrenocorticotropin (ACTH), β-lipotropin (β-LPH), and melanocyte-stimulating hormone (MSH). The ...
and melanotrope A melanotroph (or melanotrope) is a cell in the pituitary gland that generates melanocyte-stimulating hormone (α‐MSH) from its precursor pro-opiomelanocortin
Pro-opiomelanocortin (POMC) is a precursor polypeptide with 241 amino acid residues. ...
s. α-neo-endorphin
α-Neoendorphin is an endogenous opioid peptide with a decapeptide structure and the amino acid sequence tyrosine, Tyr-glycine, Gly-Gly-phenylalanine, Phe-leucine, Leu-arginine, Arg-lysine, Lys-Tyr-proline, Pro-Lys.
α-neoendorphin is a neuropep ...
is also expressed in POMC cells in the arcuate nucleus.
met-enkephalin
Met-enkephalin, also known as metenkefalin (INN), sometimes referred to as opioid growth factor (OGF), is a naturally occurring, endogenous opioid peptide that has opioid effects of a relatively short duration. It is one of the two forms of enkep ...
is widely distributed in the CNS and in immune cells; etenkephalin is a product of the proenkephalin
Introduction
Proenkephalin (PENK), formerly known as proenkephalin A (since proenkephalin B was renamed prodynorphin), is an endogenous opioid polypeptide hormone which, via proteolyic cleavage, produces the enkephalin peptides etnkephal ...
gene, and acts through μ and δ-opioid receptor
The δ-opioid receptor, also known as delta opioid receptor or simply delta receptor, abbreviated DOR or DOP, is an inhibitory 7-transmembrane G-protein coupled receptor coupled to the G protein Gi/G0 and has enkephalins as its endogenous lig ...
s. leu-enkephalin
Leu-enkephalin is an endogenous opioid peptide neurotransmitter with the amino acid sequence Tyr-Gly-Gly-Phe-Leu that is found naturally in the brains of many animals, including humans. It is one of the two forms of enkephalin; the other is met-e ...
, also a product of the proenkephalin gene, acts through δ-opioid receptors.
Dynorphin
Dynorphins (Dyn) are a class of opioid peptides that arise from the precursor protein prodynorphin. When prodynorphin is cleaved during processing by proprotein convertase 2 (PC2), multiple active peptides are released: dynorphin A, dynorphin B, a ...
acts through κ-opioid receptor
The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP, is a G protein-coupled receptor that in humans is encoded by the ''OPRK1'' gene. The KOR is coupled to the G protein Gi/G0 and is one of four related receptors that bind op ...
s, and is widely distributed in the CNS, including in the spinal cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...
and hypothalamus
The hypothalamus () is a part of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamu ...
, including in particular the arcuate nucleus
The arcuate nucleus of the hypothalamus (also known as ARH, ARC, or infundibular nucleus) is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. The arcuate nucleus includes several ...
and in both oxytocin
Oxytocin (Oxt or OT) is a peptide hormone and neuropeptide normally produced in the hypothalamus and released by the posterior pituitary. It plays a role in social bonding, reproduction, childbirth, and the period after childbirth. Oxytocin ...
and vasopressin
Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, is a hormone synthesized from the AVP gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travel ...
neurons in the supraoptic nucleus
The supraoptic nucleus (SON) is a nucleus of magnocellular neurosecretory cells in the hypothalamus of the mammalian brain. The nucleus is situated at the base of the brain, adjacent to the optic chiasm. In humans, the SON contains about 3,000 ne ...
.
Endomorphin
Endomorphins are considered to be natural opioid neurotransmitters central to pain relief. The two known endomorphins, endomorphin-1 and endomorphin-2, are tetrapeptides, consisting of Tyr-Pro-Trp-Phe and Tyr-Pro-Phe-Phe amino acid sequences resp ...
acts through μ-opioid receptors, and is more potent than other endogenous opioids at these receptors.
Opium alkaloids and derivatives
Opium alkaloids
Phenanthrene
Phenanthrene is a polycyclic aromatic hydrocarbon (PAH) with formula C14H10, consisting of three fused benzene rings. It is a colorless, crystal-like solid, but can also appear yellow. Phenanthrene is used to make dyes, plastics and pesticides, e ...
s naturally occurring in (opium
Opium (or poppy tears, scientific name: ''Lachryma papaveris'') is dried latex obtained from the seed capsules of the opium poppy ''Papaver somniferum''. Approximately 12 percent of opium is made up of the analgesic alkaloid morphine, which i ...
):
* Codeine
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...
* Morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
* Thebaine
Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, '' Thēbai'' (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically similar ...
* Oripavine
Oripavine is an opioid and the major metabolite of thebaine. It is the parent compound from which a series of semi-synthetic opioids are derived, which includes the compounds etorphine and buprenorphine. Although its analgesic potency is compar ...
Preparations of mixed opium alkaloids
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar st ...
, including papaveretum
Papaveretum (BAN) is a preparation containing a mixture of hydrochloride salts of opium alkaloids. Since 1993, papaveretum has been defined in the British Pharmacopoeia (BP) as a mixture of 253 parts morphine hydrochloride, 23 parts papaverine hy ...
, are still occasionally used.
Esters of morphine
* Diacetylmorphine
Heroin, also known as diacetylmorphine and diamorphine among other names, is a potent opioid mainly used as a recreational drug for its euphoric effects. Medical grade diamorphine is used as a pure hydrochloride salt. Various white and brown ...
(morphine diacetate; heroin)
* Nicomorphine
Nicomorphine (Vilan, Subellan, Gevilan, MorZet) is the 3,6-dinicotinate ester of morphine. It is a strong opioid agonist analgesic two to three times as potent as morphine with a side effect profile similar to that of dihydromorphine, morphine, an ...
(morphine dinicotinate)
* Dipropanoylmorphine
Dipropanoylmorphine (Dipropionylmorphine in U.S. English) is an opiate derivative, the 3,6-dipropanoyl ester of morphine. It was developed in 1972 as an analgesic. It is rarely used in some countries for the relief of severe pain such as that cause ...
(morphine dipropionate)
* Diacetyldihydromorphine
Diacetyldihydromorphine (also known as Paralaudin, dihydroheroin, acetylmorphinol) is a potent opiate derivative developed in Germany in 1928 which is rarely used in some countries for the treatment of severe pain such as that caused by terminal c ...
* Acetylpropionylmorphine
Acetylpropionylmorphine is an opiate analogue that is an ester of morphine. It was developed in the early 1900s after first being synthesised in Great Britain in 1875 but shelved along with heroin and various other esters of morphine. Acetylpropi ...
* Desomorphine
Desomorphine is a semi-synthetic opioid commercialized by Roche, with powerful, fast-acting effects, such as sedation and analgesia. It was first discovered and patented by a German team working for Knoll in 1920 but was not generally recognized ...
* Methyldesorphine
* Dibenzoylmorphine
Dibenzoylmorphine is an opiate analogue that is a derivative of morphine. It was developed in the early 1900s after first having been synthesised in 1875 in the UK by the CR Alders Wright organisation at Bayer, along with various other esters of ...
Ethers of morphine
* Dihydrocodeine
Dihydrocodeine is a semi- synthetic opioid analgesic prescribed for pain or severe dyspnea, or as an antitussive, either alone or compounded with paracetamol (acetaminophen) (as in co-dydramol) or aspirin. It was developed in Germany in 1908 an ...
* Ethylmorphine
Ethylmorphine (also known as codethyline, dionine, and ethyl morphine) is an opioid analgesic and antitussive.
Side effects
Adverse effects are similar to other opioids and include drowsiness, constipation, vertigo, nausea, vomiting, and respirat ...
* Heterocodeine
Heterocodeine (6-methoxymorphine) is an opiate derivative, the 6-methyl ether of morphine, and a chemical structure, structural isomer of codeine; it is called "hetero-" because it is the reverse isomer of codeine. Heterocodeine was first synthes ...
Semi-synthetic alkaloid derivatives
* Buprenorphine
Buprenorphine is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection (intravenous and subcutaneous), as a skin patch (transdermal), ...
* Etorphine
Etorphine (M99) is a semi-synthetic opioid possessing an analgesic potency approximately 1,000–3,000 times that of morphine. It was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather the r ...
* Hydrocodone
Hydrocodone, also known as dihydrocodeinone, is an opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe en ...
* Hydromorphone
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...
* Oxycodone
Oxycodone, sold under various brand names such as Roxicodone and OxyContin (which is the extended release form), is a strong, semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and a commonly ...
(sold as OxyContin)
* Oxymorphone
Oxymorphone (sold under the brand names Numorphan and Opana among others) is a highly potent opioid analgesic indicated for treatment of severe pain. Pain relief after injection begins after about 5–10 minutes, after oral administration it beg ...
Synthetic opioids
Anilidopiperidines
* Fentanyl
Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocaine ...
(see also list of fentanyl analogues
This is a list of fentanyl analogues (sometimes referred to as Fentalogs), including both compounds developed by pharmaceutical companies for legitimate medical use, and those which have been sold as designer drugs and reported to national drug co ...
)
* Alphamethylfentanyl
* Alfentanil
Alfentanil (R-39209, trade name Alfenta, Rapifen in Australia) is a potent but short-acting synthetic opioid analgesic medication, drug, used for anaesthesia in surgery. It is an analogue of fentanyl with around one-fourth to one-tenth the potency ...
* Sufentanil
Sufentanil, sold under the brand names Dsuvia and Sufenta, is a synthetic opioid analgesic drug approximately 5 to 10 times as potent as its parent drug, fentanyl, and 500 times as potent as morphine. Structurally, sufentanil differs from fen ...
* Remifentanil
Remifentanil is a potent, short-acting synthetic opioid analgesic drug. It is given to patients during surgery to relieve pain and as an adjunct to an anaesthetic. Remifentanil is used for sedation as well as combined with other medications fo ...
* Carfentanyl
Carfentanil or carfentanyl, sold under the brand name Wildnil, is a very potent opioid analgesic which is used in veterinary medicine to anesthetize large animals such as elephants and rhinoceroses. It is typically administered in this context ...
* Ohmefentanyl
Ohmefentanyl (also known as β-hydroxy-3-methylfentanyl, OMF and RTI-4614-4) is an extremely potent opioid analgesic drug which selectively binds to the µ-opioid receptor.
There are eight possible stereoisomers of ohmefentanyl. These stereois ...
Benzimidazoles
Benzimidazoles opioids are also known as nitazenes.
* Metodesnitazene
Metodesnitazene (also known as Metazene) is a benzimidazole derivative with opioid effects, though unlike related compounds such as metonitazene and etodesnitazene which are many times more potent, metodesnitazene is only around the same potency ...
(Metazene)
* Etodesnitazene
Etodesnitazene (Desnitroetonitazene, Etazen, Etazene, Etazone) is a benzimidazole derived opioid analgesic drug, which was originally developed in the late 1950s alongside etonitazene and a range of related derivatives. It is many times less pote ...
(Etazene)
* Metonitazene
Metonitazene is an analgesic compound related to etonitazene, which was first reported in 1957, and has been shown to have approximately 100 times the potency of morphine by central routes of administration, but if used orally it has been shown t ...
* Etonitazene
Etonitazene is an analgesic drug, first reported in 1957, that has been shown to have approximately 1,000 to 1,500 times the potency of morphine in animals.
Because it is characterized by a strong dependency potential and a tendency to produce pr ...
* Etonitazepyne
Etonitazepyne (N-Pyrrolidino Etonitazene) is a benzimidazole derivative with potent opioid effects which has been sold over the internet as a designer drug and linked to numerous cases of overdose.
See also
* Etazene
* Etonitazepipne
* Isoto ...
* Etonitazepipne
Etonitazepipne (N-Piperidino Etonitazene) is a benzimidazole derivative with opioid effects around 100 times more potent than morphine, which has been sold over the internet as a designer drug.
See also
* Etazene
* Etonitazepyne
* Isotonitazen ...
* Isotonitazene
Isotonitazene is a benzimidazole derived opioid analgesic drug related to etonitazene, which has been sold as a designer drug. It has only around half the potency of etonitazene in animal studies, but it is likely even less potent in humans as ...
* Clonitazene
Clonitazene is an opioid analgesic of approximately three times the potency of morphine. It is related to etonitazene
Etonitazene is an analgesic drug, first reported in 1957, that has been shown to have approximately 1,000 to 1,500 times the po ...
Phenylpiperidines
* Pethidine
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a synthetic opioid analgesic, pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemis ...
(meperidine)
* Ketobemidone
Ketobemidone, sold under the brand name Ketogan among others, is a powerful synthetic opioid painkiller. Its effectiveness against pain is in the same range as morphine, and it also has some NMDA-antagonist properties imparted, in part, by its m ...
* MPPP
Desmethylprodine or 1-methyl-4-phenyl-4-propionoxypiperidine (MPPP, Ro 2-0718) is an opioid analgesic drug developed in the 1940s by researchers at Hoffmann-La Roche. Desmethylprodine has been labeled by the DEA as a Schedule I drug in the U ...
* Allylprodine
Allylprodine is an opioid analgesic that is an analog of prodine. It was discovered by Hoffman-La Roche in 1957 during research into the related drug pethidine. Derivatives were tested to prove the theory that phenolic & non-phenolic opioids bind ...
* Prodine
Prodine (trade names Prisilidine and Nisentil) is an opioid analgesic that is an analog of pethidine (meperidine). It was developed in Germany in the late 1940s.
There are two isomers of the trans form of prodine, alphaprodine and betaprodine ...
* PEPAP
PEPAP (phenethylphenylacetoxypiperidine) is an opioid analgesic that is an analog of pethidine (meperidine).
It is related to the drug MPPP, with an ''N''-phenethyl group in place of the ''N''-methyl substitution and an acetate ester rather th ...
* Promedol
Diphenylpropylamine derivatives
* Propoxyphene
Dextropropoxyphene is an analgesic in the opioid category, patented in 1955 and manufactured by Eli Lilly and Company. It is an optical isomer of levopropoxyphene. It is intended to treat mild pain and also has antitussive (cough suppressant) a ...
* Dextropropoxyphene
Dextropropoxyphene is an analgesic in the opioid category, patented in 1955 and manufactured by Eli Lilly and Company. It is an optical isomer of levopropoxyphene. It is intended to treat mild pain and also has antitussive (cough suppressant) a ...
* Dextromoramide
Dextromoramide (Palfium, Palphium, Jetrium, Dimorlin) is a powerful opioid analgesic approximately three times more potent than morphine but shorter acting. It is subject to drug prohibition regimes, both internationally through UN treaties and b ...
* Bezitramide
Bezitramide is an opioid analgesic. Bezitramide itself is a prodrug which is readily hydrolyzed in the gastrointestinal tract to its active metabolite, despropionyl-bezitramide. Bezitramide was discovered at Janssen Pharmaceutica in 1961. It is m ...
* Piritramide
Piritramide(R-3365, trade names Dipidolor, Piridolan, Pirium and others) is a synthetic opioid analgesic (narcotic painkiller) that is marketed in certain European countries including: Austria, Belgium, Czech Republic, Slovenia, Germany and the ...
* Methadone
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...
* Dipipanone
Dipipanone (Pipadone) is a strong opioid analgesic drug, used for acute pain by mouth (PO) for adults - initially 10 mg every 6 hours, then increased if necessary up to 30 mg every 6 hours, with the dose to be increased gradually. It is often use ...
* Levomethadyl acetate
Levacetylmethadol (INN), levomethadyl acetate (USAN), OrLAAM (trade name) or levo-α-acetylmethadol (LAAM) is a synthetic opioid similar in structure to methadone. It has a long duration of action due to its active metabolites.
Medical uses
LAA ...
(LAAM)
* Difenoxin
Difenoxin (Motofen, R-15403) is an opioid drug used, often in combination with atropine, to treat diarrhea. It is the principal metabolite of diphenoxylate.
It was first approved in the US in 1978 and in 1980 in the former West Germany.
Difeno ...
* Diphenoxylate
Diphenoxylate is a centrally active opioid drug of the phenylpiperidine series that is used as a combination drug with atropine for the treatment of diarrhea. Diphenoxylate is an opioid and acts by slowing intestinal contractions; the atropine i ...
* Loperamide
Loperamide, sold under the brand name Imodium, among others,Drugs.co Page accessed September 4, 2015 is a medication used to decrease the frequency of diarrhea. It is often used for this purpose in inflammatory bowel disease and short bowel synd ...
(does cross the blood–brain barrier but is quickly pumped into the non-central nervous system by P-Glycoprotein. Mild opiate withdrawal in animal models exhibits this action after sustained and prolonged use including rhesus monkeys, mice, and rats.)
Benzomorphan derivatives
* Dezocine
Dezocine, sold under the brand name Dalgan, is an atypical opioid analgesic which is used in the treatment of pain. It is used by intravenous infusion and intramuscular injection.
Dezocine is an opioid receptor modulator, acting as a partial ...
—agonist/antagonist
* Pentazocine
Pentazocine, sold under the brand name Talwin among others, is a painkiller used to treat moderate to severe pain. It is believed to work by activating (agonizing) κ-opioid receptors (KOR) and μ-opioid receptors (MOR). As such it is called an ...
—agonist/antagonist
* Phenazocine
Phenazocine (brand names Prinadol, Narphen) is an opioid analgesic drug, which is related to pentazocine and has a similar profile of effects.
Effects of phenazocine include analgesia and euphoria, also may include dysphoria and hallucinations at ...
Oripavine derivatives
* Buprenorphine
Buprenorphine is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection (intravenous and subcutaneous), as a skin patch (transdermal), ...
—partial agonist
* Dihydroetorphine
Dihydroetorphine was developed by K. W. Bentley at McFarlan-Smith in the 1960s and is a potent opioid analgesic used mainly in China. It is a derivative of the better-known opioid etorphine, a very potent veterinary painkiller and anesthetic med ...
* Etorphine
Etorphine (M99) is a semi-synthetic opioid possessing an analgesic potency approximately 1,000–3,000 times that of morphine. It was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather the r ...
Morphinan derivatives
* Butorphanol
Butorphanol is a morphinan-type synthetic agonist–antagonist opioid analgesic developed by Bristol-Myers. Butorphanol is most closely structurally related to levorphanol. Butorphanol is available as the tartrate salt in injectable, tablet, an ...
—agonist/antagonist
* Nalbuphine
Nalbuphine, sold under the brand names Nubain among others, is an opioid analgesic which is used in the treatment of pain. It is given by injection into a vein, muscle, or fat.
Side effects of nalbuphine include sedation, sweatiness, clammin ...
—agonist/antagonist
* Levorphanol
Levorphanol (brand name Levo-Dromoran) is an opioid medication used to treat moderate to severe pain. It is the levorotatory enantiomer of the compound racemorphan. Its dextrorotatory counterpart is dextrorphan.
It was first described in German ...
* Levomethorphan
Levomethorphan (LVM) ( INN, BAN) is an opioid analgesic of the morphinan family that has never been marketed. It is the L-stereoisomer of racemethorphan (methorphan). The effects of the two isomers of the racemethorphan are quite different, with ...
* Racemethorphan
Methorphan comes in two isomeric forms, each with differing pharmacology and effects:
* Dextromethorphan - An over-the-counter cough suppressant, as well as dissociative hallucinogen.
* Levomethorphan - A potent opioid analgesic that was never ...
Others
* Lefetamine
Lefetamine (Santenol) is a drug which is a stimulant and also an analgesic with effects comparable to codeine.
Discovery
Lefetamine-related 1,2-diphenylethylamines were invented in the 1940s and showed weak analgesic activity.
It was inv ...
* Meptazinol
Meptazinol (trade name Meptid) is an opioid analgesic developed by Wyeth in the 1970s. Indications for use in moderate to severe pain, most commonly used to treat pain in obstetrics (childbirth).
Meptazinol is a 3-phenylazepane derivative, where ...
* Mitragynine
Mitragynine is an indole-based alkaloid and the most abundant active alkaloid in the Southeast Asian plant ''Mitragyna speciosa'', commonly known as '' kratom.'' The total alkaloid concentration in dried leaves ranges from 0.5 to 1.5%. In Thai va ...
* Tilidine
Tilidine, or tilidate (brand names: Tilidin, Valoron, Tetova and Valtran) is a synthetic opioid painkiller, used mainly in Belgium, Bulgaria, Germany, Luxembourg, South Africa and Switzerland for the treatment of moderate to severe pain, both acu ...
* Tramadol
Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an h ...
* Tapentadol
Tapentadol, brand names Nucynta among others, is a centrally acting opioid analgesic of the benzenoid class with a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI). Analgesia occurs wit ...
* Eluxadoline
Eluxadoline, sold under the brand names Viberzi and Truberzi, is a medication taken by mouth for the treatment of diarrhea and abdominal pain in individuals with diarrhea-predominant irritable bowel syndrome (IBS-D). It was approved for use in t ...
* AP-237
Bucinnazine (AP-237, 1-butyryl-4-cinnamylpiperazine) is an opioid analgesic drug that was widely used in China to treat pain in cancer patients as of 1986. It is one of the most potent compounds among a series of piperazine-amides first synthesiz ...
* 7-Hydroxymitragynine
7-Hydroxymitragynine is a terpenoid indole alkaloid from the plant ''Mitragyna speciosa'', commonly known as Kratom. It is often referred to as ‘7-OH’. It was first described in 1994 and is a natural product derived from the mitragynine prese ...
Allosteric modulators
Plain allosteric modulator
In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a Receptor (biochemistry), receptor to change that receptor's response to stimulus. Some of them, like benzodiazepines, are drugs. The site that an allos ...
s do not belong to the opioids, instead they are classified as opioidergic
An opioidergic agent (or drug) is a chemical which functions to directly modulate the opioid neuropeptide systems (i.e., endorphin, enkephalin, dynorphin, nociceptin) in the body or brain. Examples include opioid analgesics such as morphine and ...
s.
Opioid antagonist
An opioid antagonist, or opioid receptor antagonist, is a receptor antagonist that acts on one or more of the opioid receptors.
Naloxone and naltrexone are commonly used opioid antagonist drugs which are competitive antagonists that bind to the o ...
s
* Nalmefene
Nalmefene is an opioid antagonist medication used in the management of opioid overdose and alcohol dependence. It is taken by mouth.
Nalmefene is an opiate derivative similar in both structure and activity to the opioid antagonist naltrexone. ...
* Naloxone
Naloxone, sold under the brand names Narcan (4 mg) and Kloxxado (8 mg) among others, is a medication used to reverse or reduce the effects of opioids. It is commonly used to counter decreased breathing in opioid overdose. Effects begin within ...
* Naltrexone
Naltrexone, sold under the brand name Revia among others, is a medication primarily used to manage alcohol or opioid use disorder by reducing cravings and feelings of euphoria associated with substance use disorder. It has also been found t ...
* Methylnaltrexone
Methylnaltrexone (MNTX, brand name Relistor), used in form of methylnaltrexone bromide (INN, USAN, BAN), is a medication that acts as a peripherally acting μ-opioid receptor antagonist that acts to reverse some of the side effects of opioid dr ...
(Methylnaltrexone is only peripherally active as it does not cross the blood–brain barrier in sufficient quantities to be centrally active. As such, it can be considered the antithesis of loperamide
Loperamide, sold under the brand name Imodium, among others,Drugs.co Page accessed September 4, 2015 is a medication used to decrease the frequency of diarrhea. It is often used for this purpose in inflammatory bowel disease and short bowel synd ...
.)
* Naloxegol
Naloxegol (INN; PEGylated naloxol; trade names Movantik and Moventig) is a peripherally acting μ-opioid receptor antagonist developed by AstraZeneca, licensed from Nektar Therapeutics, for the treatment of opioid-induced constipation. It was app ...
(Naloxegol is only peripherally active as it does not cross the blood–brain barrier in sufficient quantities to be centrally active. As such, it can be considered the antitheses of loperamide
Loperamide, sold under the brand name Imodium, among others,Drugs.co Page accessed September 4, 2015 is a medication used to decrease the frequency of diarrhea. It is often used for this purpose in inflammatory bowel disease and short bowel synd ...
.)
Tables of opioids
Table of morphinan opioids
Table of non-morphinan opioids
See also
* Froehde reagent The Froehde reagent is used as a simple spot-test to presumptively identify alkaloids, especially opioids, as well as other compounds. It is composed of a mixture of molybdic acid or a molybdate salt dissolved in hot, concentrated sulfuric acid, whi ...
* Opiate comparison
An equianalgesic chart is a conversion chart that lists equivalent doses of analgesics (drugs used to relieve pain). Equianalgesic charts are used for calculation of an equivalent dose (a dose which would offer an equal amount of analgesia) betwee ...
* Opioid epidemic
The opioid epidemic, also referred to as the opioid crisis, is the rapid increase in the overuse, misuse/abuse, and overdose deaths attributed either in part or in whole to the class of drugs opiates/opioids since the 1990s. It includes the sign ...
*Opioid tapering
Opioid tapering is the reduction of opioid
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression o ...
References
External links
Opioid Withdrawal Symptoms
Information about Opioid and opiate withdrawal issues
*
World Health Organization guidelines for the availability and accessibility of controlled substances
* ttp://whqlibdoc.who.int/hq/2011/WHO_EMP_MAR_2011.4_eng.pdf Reference list to the previous publication
Links to all language versions of the previous publication
* Video: Opioid side effect
(Vimeo)(YouTube)
A short educational film about the practical management of opioid side effects.
{{authority control
Morphine
Articles containing video clips