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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 Germany in 1946. The drug has been in medical use in the United States since 1953. Pharmacology Levorphanol acts predominantly as an agonist of the μ-opioid receptor (MOR), but is also an agonist of the δ-opioid receptor (DOR), κ-opioid receptor (KOR), and the nociceptin receptor (NOP), as well as an NMDA receptor antagonist and a serotonin-norepinephrine reuptake inhibitor (SNRI). Levorphanol, similarly to certain other opioids, also acts as a glycine receptor antagonist and GABA receptor antagonist at very high concentrations. Levorphanol is 6 to 8 times as potent as morphine at the MOR. Relative to morphine, levorphanol lacks complete cross-tolerance and possesses greater intrinsic activity at the MOR. The duration of action is general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 of diarrhea, replacement therapy for opioid use disorder, reversing opioid overdose, and suppressing cough. Extremely potent opioids such as carfentanil are approved only for veterinary use. Opioids are also frequently used non-medically for their euphoric effects or to prevent withdrawal. Opioids can cause death and have been used for executions in the United States. Side effects of opioids may include itchiness, sedation, nausea, respiratory depression, constipation, and euphoria. Long-term use can cause tolerance, meaning that increased doses are required to achieve the same effect, and physical dependence, meaning that abruptly discontinuing the drug leads to unpleasant withdrawal symptoms. The euphoria attracts recreational use, and frequent, escalating recreational use of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 is referred to as dissociative anesthesia. Several synthetic opioids function additionally as NMDAR-antagonists, such as pethidine, levorphanol, methadone, dextropropoxyphene, tramadol and ketobemidone. Some NMDA receptor antagonists, such as ketamine, dextromethorphan (DXM), phencyclidine (PCP), methoxetamine (MXE), and nitrous oxide (N2O), are sometimes used as recreational drugs, for their dissociative, hallucinogenic, and euphoriant properties. When used recreationally, they are classified as dissociative drugs. Uses and effects NMDA receptor antagonists induce a state called dissociative anesthesia, marked by catalepsy, amnesia, and analgesia. Ketamine is a favored anesthetic for emergency patients with unknown medical history and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 is a member of the opioid subfamily of G protein-coupled receptors whose natural ligand is the 17 amino acid neuropeptide known as nociceptin (N/OFQ). This receptor is involved in the regulation of numerous brain activities, particularly instinctive and emotional behaviors. Antagonists targeting NOP are under investigation for their role as treatments for depression and Parkinson's disease, whereas NOP agonists have been shown to act as powerful, non-addictive painkillers in non-human primates. Although NOP shares high sequence identity (~60%) with the ‘classical’ opioid receptors μ-OP (MOP), κ-OP (KOP), and δ-OP (DOP), it possesses little or no affinity for opioid peptides or morphine-like compounds. Likewise, classical opioid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 opioid-like compounds in the brain and are responsible for mediating the effects of these compounds. These effects include altering nociception, consciousness, motor control, and mood. Dysregulation of this receptor system has been implicated in alcohol and drug addiction. The KOR is a type of opioid receptor that binds the opioid peptide dynorphin as the primary endogenous ligand (substrate naturally occurring in the body). In addition to dynorphin, a variety of natural alkaloids, terpenes and synthetic ligands bind to the receptor. The KOR may provide a natural addiction control mechanism, and therefore, drugs that target this receptor may have therapeutic potential in the treatment of addiction. There is evidence that distribution ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 and/or episodic (paroxysmal) components. The latter resemble stabbings or electric shocks. Common qualities include burning or coldness, "pins and needles" sensations, numbness and itching. Up to 7%-8% of the European population is affected, and in 5% of persons it may be severe. Neuropathic pain may result from disorders of the peripheral nervous system or the central nervous system (brain and spinal cord). Thus, neuropathic pain may be divided into peripheral neuropathic pain, central neuropathic pain, or mixed (peripheral and central) neuropathic pain. Neuropathic pain may occur in isolation or in combination with other forms of pain. Medical treatments focus on identifying the underlying cause and relieving pain. In cases of neuropathy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. Dextrorphan is produced by O-demethylation of dextromethorphan by CYP2D6. Dextrorphan is an NMDA antagonist and contributes to the psychoactive effects of dextromethorphan. Pharmacology Pharmacodynamics The pharmacology of dextrorphan is similar to that of dextromethorphan (DXM). However, dextrorphan is much more potent as an NMDA receptor antagonist as well much less active as a serotonin reuptake inhibitor, but retains DXM's activity as a norepinephrine reuptake inhibitor. It also has more affinity for the opiod receptors than dextromethorphan, significantly so at high doses. Pharmacokinetics Dextrorphan has a notably longer elimination half-life than its parent compound, and therefore has a tendency to accumulate in the blood after repe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatic
The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it is located in the right upper quadrant of the abdomen, below the diaphragm. Its other roles in metabolism include the regulation of glycogen storage, decomposition of red blood cells, and the production of hormones. The liver is an accessory digestive organ that produces bile, an alkaline fluid containing cholesterol and bile acids, which helps the breakdown of fat. The gallbladder, a small pouch that sits just under the liver, stores bile produced by the liver which is later moved to the small intestine to complete digestion. The liver's highly specialized tissue, consisting mostly of hepatocytes, regulates a wide variety of high-volume biochemical reactions, including the synthesis and breakdown of small and complex molecules, many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duration Of Action
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 example, infection). Pharmacodynamics and pharmacokinetics are the main branches of pharmacology, being itself a topic of biology interested in the study of the interactions between both endogenous and exogenous chemical substances with living organisms. In particular, pharmacodynamics is the study of how a drug affects an organism, whereas pharmacokinetics is the study of how the organism affects the drug. Both together influence dosing, benefit, and adverse effects. Pharmacodynamics is sometimes abbreviated as PD and pharmacokinetics as PK, especially in combined reference (for example, when speaking of PK/PD models). Pharmacodynamics places particular emphasis on dose–response relationships, that is, the relationships between drug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylpiperidine
Phenylpiperidines are chemical compounds with a phenyl moiety directly attached to piperidine. There are a variety of pharmacological effects associated with phenylpiperidines including morphine-like activity or other central nervous system effects. Methylphenidate is a ''benzyl In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure . Benzyl features a benzene ring () attached to a methylene group () group. Nomenclature In IUPAC nomenclature, the prefix benzyl refers to a substi ...''piperidine. References Piperidines {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 or other opioids. Prescribed for daily use, the medicine relieves cravings and removes withdrawal symptoms. Detoxification using methadone can be accomplished in less than a month, or it may be done gradually over as long as six months. While a single dose has a rapid effect, maximum effect can take up to five days of use. The pain-relieving effects last about six hours after a single dose. After long-term use, in people with normal liver function, effects last 8 to 36 hours. Methadone is usually taken by mouth and rarely by injection into a muscle or vein. Side effects are similar to those of other opioids. These frequently include dizziness, sleepiness, vomiting, and sweating. Serious risks include opioid abuse and respiratory depre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-tolerance
Cross-tolerance is a phenomenon that occurs when tolerance to the effects of a certain drug produces tolerance to another drug. It often happens between two drugs with similar functions or effects—for example, acting on the same cell receptor or affecting the transmission of certain neurotransmitters. Cross-tolerance has been observed with pharmaceutical drugs such as anti-anxiety agents and illicit substances, and sometimes the two of them together. Often, a person who uses one drug can be tolerant to a drug that has a completely different function.Kolb, Bryan, and Ian Whishaw. An Introduction to Brain and Behavior. New York: Worth Publishers, 2014. Print. This phenomenon allows one to become tolerant to a drug that they have never used before. Drug classifications and cross-tolerance Anxiolytics and sedatives Excitation of the GABA receptor produces an influx of negatively charged chloride ions, which hyperpolarizes the neuron and makes it less likely to give rise to an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
