Anticholinergics (anticholinergic agents) are substances that block the action of the

neurotransmitter A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell. Neuro ...

called

acetylcholine Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Part ...

(ACh) at

synapse In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. Synapses are essential to the transmission of nervous impulses from ...

s 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 ...

. These agents inhibit the

parasympathetic nervous system The parasympathetic nervous system (PSNS) is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of ...

by selectively blocking the binding of ACh to its receptor in nerve cells. The

nerve fiber An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action po ...

s of the parasympathetic system are responsible for the involuntary movement of smooth muscles present in 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 ...

, urinary tract,

lungs The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of th ...

sweat gland Sweat glands, also known as sudoriferous or sudoriparous glands, , are small tubular structures of the skin that produce sweat. Sweat glands are a type of exocrine gland, which are glands that produce and secrete substances onto an epithelial sur ...

s, and many other parts of the body. In broad terms, anticholinergics are divided into two categories in accordance with their specific targets in the central and peripheral nervous system and at the neuromuscular junction: antimuscarinic agents, and

antinicotinic A nicotinic antagonist is a type of anticholinergic drug that inhibits the action of acetylcholine (ACh) at nicotinic acetylcholine receptors. These compounds are mainly used for peripheral muscle paralysis in surgery, the classical agent of this t ...

agents (

ganglionic blockers A ganglionic blocker (or ganglioplegic) is a type of medication that inhibits transmission between preganglionic and postganglionic neurons in the autonomic nervous system, often by acting as a nicotinic receptor antagonist. Nicotinic acetylcholin ...

neuromuscular blockers Neuromuscular-blocking drugs block neuromuscular transmission at the neuromuscular junction, causing paralysis of the affected skeletal muscles. This is accomplished via their action on the post-synaptic acetylcholine (Nm) receptors. In clin ...

). The term "anticholinergic" is typically used to refer to antimuscarinics which competitively inhibit the binding of ACh to

muscarinic acetylcholine receptor Muscarinic acetylcholine receptors, or mAChRs, are acetylcholine receptors that form G protein-coupled receptor complexes in the cell membranes of certain neurons and other cells. They play several roles, including acting as the main end-rece ...

s; such agents do not antagonize the binding at nicotinic acetylcholine receptors at the

neuromuscular junction A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction. Muscles require innervation to ...

, although the term is sometimes used to refer to agents which do so.

Medical uses

Anticholinergic drugs are used to treat a variety of conditions: *

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 ...

(including vertigo and motion sickness-related symptoms) * Extrapyramidal symptoms, a potential side-effect of antipsychotic medications * Gastrointestinal disorders (e.g., peptic ulcers,

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 ...

, pyloro spasm,

diverticulitis Diverticulitis, specifically colonic diverticulitis, is a gastrointestinal disease characterized by inflammation of abnormal pouches—diverticula—which can develop in the wall of the large intestine. Symptoms typically include lower abdominal ...

, ulcerative colitis,

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 Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the Human nose, nose. Vomiting can be the result of ailments like Food-poisoning, foo ...

) * Genitourinary disorders (e.g., cystitis, urethritis, and prostatitis) *

Insomnia Insomnia, also known as sleeplessness, is a sleep disorder in which people have trouble sleeping. They may have difficulty falling asleep, or staying asleep as long as desired. Insomnia is typically followed by daytime sleepiness, low energy, ...

, although usually only on a short-term basis * Respiratory disorders (e.g., asthma, chronic bronchitis, and chronic obstructive pulmonary disease

OPD OPD may refer to: Police departments * Oakland Police Department, a U.S. law enforcement agency in California * Omaha Police Department, a U.S. law enforcement agency in Nebraska * Orlando Police Department, a U.S. law enforcement agency in Florida ...

* Sinus bradycardia due to a hypersensitive

vagus nerve The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and right ...

Organophosphate In organic chemistry, organophosphates (also known as phosphate esters, or OPEs) are a class of organophosphorus compounds with the general structure , a central phosphate molecule with alkyl or aromatic substituents. They can be considered a ...

based nerve agent poisoning, such as VX, sarin, tabun, and soman (atropine is favoured in conjunction with an oxime, usually pralidoxime) Anticholinergics generally have ''

antisialagogue Antisialagogues are drugs or substances that decrease the flow rate of saliva and their effect is opposite to that of sialagogues. Their origin may be both natural and synthetic. Anticholinergics generally have antisialagogue effects, and most pro ...

'' effects (decreasing saliva production), and most produce some level of sedation, both being advantageous in surgical procedures. Until the beginning of the 20th century anticholinergic drugs were widely used to treat psychiatric disorders.

Physiological effects

*Delirium (often with

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 ...

and

delusions A delusion is a false fixed belief that is not amenable to change in light of conflicting evidence. As a pathology, it is distinct from a belief based on false or incomplete information, confabulation, dogma, illusion, hallucination, or some o ...

indistinguishable from reality) *Ocular symptoms (from eye drops):

mydriasis Mydriasis is the dilation of the pupil, usually having a non-physiological cause, or sometimes a physiological pupillary response. Non-physiological causes of mydriasis include disease, trauma, or the use of certain types of drugs. Normally, as ...

pupil dilation Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve. A constriction response (miosis), is the narrowing of the pupil, which may be caused by scleral buckles or drugs such a ...

, and

acute angle-closure glaucoma Glaucoma is a group of eye diseases that result in damage to the optic nerve (or retina) and cause vision loss. The most common type is open-angle (wide angle, chronic simple) glaucoma, in which the drainage angle for fluid within the eye rem ...

in those with shallow anterior chamber * Anhidrosis, dry mouth, dry skin *Fever *Constipation *Tachycardia *Urinary retention *

Cutaneous vasodilation Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...

Clinically the most significant feature is delirium, particularly in the elderly, who are most likely to be affected by the

toxidrome A toxidrome (a portmanteau of ''toxic'' and ''syndrome'') is a syndrome caused by a dangerous level of toxins in the body. The term was coined in 1970 by Mofenson and Greensher. It is often the consequence of a drug overdose. Common symptoms incl ...

Side effects

Long-term use may increase the risk of both cognitive and physical decline. It is unclear whether they affect the risk of death generally. However, in older adults they do appear to increase the risk of death. Possible effects of anticholinergics include: * Poor coordination *

Dementia Dementia is a disorder which manifests as a set of related symptoms, which usually surfaces when the brain is damaged by injury or disease. The symptoms involve progressive impairments in memory, thinking, and behavior, which negatively affe ...

* Decreased mucus production in the nose and throat; consequent dry, sore throat * Dry-mouth with possible acceleration of dental caries * Cessation of

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 ...

; consequent decreased epidermal thermal dissipation leading to warm, blotchy, or red skin * Increased body temperature *

Pupil dilation Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve. A constriction response (miosis), is the narrowing of the pupil, which may be caused by scleral buckles or drugs such a ...

; consequent sensitivity to bright light ( photophobia) * Loss of accommodation (loss of focusing ability, blurred vision – cycloplegia) * Double-vision *

Increased heart rate 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 ...

* Tendency to be easily startled * Urinary retention * Urinary incontinence while sleeping * Diminished bowel movement, sometimes ileus (decreases motility via the

) * Increased intraocular pressure; dangerous for people with narrow-angle

glaucoma Glaucoma is a group of eye diseases that result in damage to the optic nerve (or retina) and cause vision loss. The most common type is open-angle (wide angle, chronic simple) glaucoma, in which the drainage angle for fluid within the eye rem ...

. Possible effects in the central nervous system resemble those associated with

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 ...

, and may include: * Confusion * Disorientation * Agitation *

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 ...

or dysphoria * Respiratory depression * Memory problems * Inability to concentrate * Wandering thoughts; inability to sustain a

train of thought The train of thought or track of thought refers to the interconnection in the sequence of ideas expressed during a connected discourse or thought, as well as the sequence itself, especially in discussion how this sequence leads from one idea to ...

* Incoherent speech * Irritability * Mental confusion (brain fog) * Wakeful

myoclonic jerk Myoclonus is a brief, involuntary, irregular (lacking rhythm) twitching of a muscle or a group of muscles, different from clonus, which is rhythmic or regular. Myoclonus (myo "muscle", clonic "jerk") describes a medical sign and, generally, is ...

ing * Unusual sensitivity to sudden sounds * Illogical thinking * Photophobia * Visual disturbances ** Periodic flashes of light ** Periodic changes in visual field ** Visual snow ** Restricted or "tunnel vision" * Visual, auditory, or other sensory hallucinations ** Warping or waving of surfaces and edges ** Textured surfaces ** "Dancing" lines; "spiders", insects;

form constants A form constant is one of several geometric patterns which are recurringly observed during hypnagogia, hallucinations and altered states of consciousness. History In 1926, Heinrich Klüver systematically studied the effects of mescaline (peyote ...

** Lifelike objects indistinguishable from reality ** Phantom smoking ** Hallucinated presence of people not actually there * Rarely: seizures, coma, and death *

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 ...

(severe drop in systolic blood pressure when standing up suddenly) and significantly increased risk of falls in the elderly population. Older patients are at a higher risk of experiencing CNS side effects.

Toxicity

An acute anticholinergic syndrome is reversible and subsides once all of the causative agents have been excreted. Reversible acetylcholinesterase inhibitor agents such as physostigmine can be used as an antidote in life-threatening cases. Wider use is discouraged due to the significant side effects related to cholinergic excess including seizures, muscle weakness, bradycardia, bronchoconstriction, lacrimation, salivation, bronchorrhea, vomiting, and diarrhea. Even in documented cases of anticholinergic toxicity, seizures have been reported after the rapid administration of physostigmine. Asystole has occurred after physostigmine administration for tricyclic antidepressant overdose, so a conduction delay (QRS > 0.10 second) or suggestion of tricyclic antidepressant ingestion is generally considered a contraindication to physostigmine administration.

Pharmacology

Anticholinergics are classified according to the receptors that are affected: * '' Antimuscarinic'' agents operate on the

s. The majority of anticholinergic drugs are antimuscarinics. * ''

Antinicotinic A nicotinic antagonist is a type of anticholinergic drug that inhibits the action of acetylcholine (ACh) at nicotinic acetylcholine receptors. These compounds are mainly used for peripheral muscle paralysis in surgery, the classical agent of this t ...

'' agents operate on the nicotinic acetylcholine receptors. The majority of these are non-depolarising

skeletal muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...

relaxants for surgical use that are structurally related to curare. Several are depolarizing agents.

Examples

Examples of common anticholinergics: * Antimuscarinic agents ** Antipsychotics ( clozapine, quetiapine) **

Atropine Atropine is a tropane alkaloid and anticholinergic medication used to treat certain types of nerve agent and pesticide poisonings as well as some types of slow heart rate, and to decrease saliva production during surgery. It is typically given i ...

** Benztropine ** Biperiden ** Chlorpheniramine ** Certain

SSRIs Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs increase the extracellul ...

(

Paroxetine Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...

) ** Dicyclomine ( Dicycloverine) ** Dimenhydrinate **

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 ...

Doxepin Doxepin is a medication falling in the tricyclic antidepressant (TCA) class used to treat major depressive disorder, anxiety disorders, chronic hives, and insomnia. For label updates seFDA index page for NDA 022036/ref> For hives it is a less pre ...

Doxylamine Doxylamine, sold under the brand name Unisom among others, is an antihistamine medication which is used in the treatment of insomnia and allergies. In combination with pyridoxine ( vitamin B6), it is also used to treat morning sickness in pregna ...

Flavoxate Flavoxate is an anticholinergic with antimuscarinic effects. Its muscle relaxant properties may be due to a direct action on the smooth muscle rather than by antagonizing muscarinic receptors. Clinical uses Flavoxate is used to treat urinary bl ...

Glycopyrrolate Glycopyrronium bromide is a medication of the muscarinic anticholinergic group. It does not cross the blood–brain barrier and consequently has few to no central effects. It is available in oral, intravenous, topical, and inhaled forms. It is a ...

** Glycopyrronium **

Hyoscyamine Hyoscyamine (also known as daturine or duboisine) is a naturally occurring tropane alkaloid and plant toxin. It is a secondary metabolite found in certain plants of the family Solanaceae, including henbane, mandrake, angel's trumpets, jimsonweed ...

Ipratropium Ipratropium bromide, sold under the trade name Atrovent among others, is a type of anticholinergic (SAMA: short acting muscarinic antagonist) medication which opens up the medium and large airways in the lungs. It is used to treat the symptoms ...

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 ...

** Oxitropium ** Oxybutynin ** Promethazine **

Propantheline bromide Propantheline bromide (INN) is an antimuscarinic agent used for the treatment of excessive sweating (hyperhidrosis), cramps or spasms of the stomach, intestines (gut) or bladder, and involuntary urination (enuresis). It can also be used to contro ...

Scopolamine Scopolamine, also known as hyoscine, or Devil's Breath, is a natural or synthetically produced tropane alkaloid and anticholinergic drug that is formally used as a medication for treating motion sickness and postoperative nausea and vomiting ...

Solifenacin Solifenacin, sold as the brand name Vesicare among others, is a medicine used to treat overactive bladder and neurogenic detrusor overactivity (NDO). It may help with urinary incontinence, incontinence, urinary frequency, and urinary urgency. ...

** Tolterodine **

Tiotropium Tiotropium bromide, sold under the brand name Spiriva among others, is a long-acting bronchodilator (LAMA: long acting muscarinic antagonist) used in the management of chronic obstructive pulmonary disease (COPD) and asthma. Specifically it is ...

Tricyclic antidepressants 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 ...

(28 compounds with numerous trade names) **

Trihexyphenidyl Trihexyphenidyl (THP, benzhexol, trihex, marketed as Artane and others) is an antispasmodic drug used to treat stiffness, tremors, spasms, and poor muscle control. It is an agent of the antimuscarinic class and is often used in management of Pa ...

Tropicamide Tropicamide, sold under the brand name Mydriacyl among others, is a medication used to dilate the pupil and help with examination of the eye. Specifically it is used to help examine the back of the eye. It is applied as eye drops. Effects occ ...

** Umeclidinium * Antinicotinic agents **

Bupropion Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the case ...

– Ganglion blocker **

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 ...

- Cough suppressant and ganglion blocker **

Doxacurium Doxacurium chloride (formerly recognized as BW938U80 or BW A938U) is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to provide skeletal m ...

– Nondepolarizing skeletal muscular relaxant **

Hexamethonium Hexamethonium is a non-depolarising ganglionic blocker, a nicotinic ( nAChR) receptor antagonist that acts in autonomic ganglia by binding mostly in or on the nAChR receptor, and not the acetylcholine binding site itself. It does not have a ...

– Ganglion blocker ** Mecamylamine – Ganglion blocker and occasional smoking cessation aid **

Tubocurarine Tubocurarine (also known as ''d''-tubocurarine or DTC) is a toxic alkaloid historically known for its use as an arrow poison. In the mid-1900s, it was used in conjunction with an anesthetic to provide skeletal muscle relaxation during surgery or ...

- Nondepolarizing skeletal muscular relaxant Plants of the family

Solanaceae The Solanaceae , or nightshades, are a family of flowering plants that ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of agricultural crops, medicinal plants, spices, weeds, and orn ...

contain various anticholinergic

tropane alkaloids Tropane alkaloids are a class of bicyclic .2.1alkaloids and secondary metabolites that contain a tropane ring in their chemical structure. Tropane alkaloids occur naturally in many members of the plant family Solanaceae. Certain tropane alkaloi ...

, such as

scopolamine Scopolamine, also known as hyoscine, or Devil's Breath, is a natural or synthetically produced tropane alkaloid and anticholinergic drug that is formally used as a medication for treating motion sickness and postoperative nausea and vomiting ...

atropine Atropine is a tropane alkaloid and anticholinergic medication used to treat certain types of nerve agent and pesticide poisonings as well as some types of slow heart rate, and to decrease saliva production during surgery. It is typically given i ...

, and

hyoscyamine Hyoscyamine (also known as daturine or duboisine) is a naturally occurring tropane alkaloid and plant toxin. It is a secondary metabolite found in certain plants of the family Solanaceae, including henbane, mandrake, angel's trumpets, jimsonweed ...

. Physostigmine is one of only a few drugs that can be used as an antidote for anticholinergic poisoning.

Nicotine Nicotine is a natural product, naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and ''Duboisia hopwoodii'') and is widely used recreational drug use, recreationally as a stimulant and anxiolytic. As ...

also counteracts anticholinergics by activating nicotinic acetylcholine receptors. Caffeine (although an

adenosine Adenosine ( symbol A) is an organic compound that occurs widely in nature in the form of diverse derivatives. The molecule consists of an adenine attached to a ribose via a β-N9-glycosidic bond. Adenosine is one of the four nucleoside building ...

receptor 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 rece ...

) can counteract the anticholinergic symptoms by reducing sedation and increasing acetylcholine activity, thereby causing alertness and arousal.

Psychoactive uses

When a significant amount of an anticholinergic is taken into the body, a toxic reaction known as acute anticholinergic syndrome may result. This may happen accidentally or intentionally as a consequence of either

recreational Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure ...

or entheogenic drug use, though many users find the side effects to be exceedingly unpleasant and not worth the recreational effects they experience. In the context of recreational use, anticholinergics are often called deliriants.

Plant sources

The most common plants containing anticholinergic

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

, and

among others) are: *''

Atropa belladonna ''Atropa belladonna'', commonly known as belladonna or deadly nightshade, is a toxic perennial herbaceous plant in the nightshade family Solanaceae, which also includes tomatoes, potatoes, and eggplant (aubergine). It is native to Europe, North ...

'' (deadly nightshade) *'' Brugmansia'' species *''

Datura ''Datura'' is a genus of nine species of highly poisonous, vespertine-flowering plants belonging to the nightshade family Solanaceae. They are commonly known as thornapples or jimsonweeds, but are also known as devil's trumpets (not to be conf ...

'' species *''

Garrya ''Garrya'' is a genus of flowering plants in the family Garryaceae native to Mexico, the western United States, Central America and the Greater Antilles. Common names include silk tassel and tassel bush. They are evergreen dioecious wind-pollina ...

'' species *'' Hyoscyamus niger'' (henbane) *'' Mandragora officinarum'' (mandrake)

Use as a deterrent

Several narcotic and

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 ...

-containing drug preparations, such as those containing hydrocodone and

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 ...

are combined with an anticholinergic agent to deter intentional misuse. Examples include

Hydromet Hydrometallurgy is a technique within the field of extractive metallurgy, the obtaining of metals from their ores. Hydrometallurgy involve the use of aqueous solutions for the recovery of metals from ores, concentrates, and recycled or residual m ...

Hycodan Hydrocodone/homatropine, sold under the brand name Tussigon among others, is a fixed-dose combination medication used for the treatment of cough. It contains hydrocodone, as the bitartrate, an opioid agonist; and homatropine, as the methylbrom ...

(hydrocodone/homatropine),

Lomotil Diphenoxylate/atropine, also known as co-phenotrope, is a combination of the medications diphenoxylate and atropine, used to treat diarrhea. It should not be used in those in whom ''Clostridioides difficile'' infection is a concern. It is take ...

(diphenoxylate/atropine) and Tussionex (hydrocodone polistirex/chlorpheniramine). However, it is noted that opioid/antihistamine combinations are used clinically for their synergistic effect in the management of pain and maintenance of dissociative

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), ...

(sedation) in such preparations as Meprozine ( meperidine/ promethazine) and

Diconal 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 ...

( dipipanone/ cyclizine), which act as strong anticholinergic agents.

References

{{Acetylcholine metabolism and transport modulators * Medical mnemonics