Trihexyphenidyl (CED0004997)

Record Information

Version

1.0

Creation Date

2009-07-21 20:26:45 UTC

Update Date

2026-05-14 16:36:59 UTC

SynCED ID

CED0004997

Secondary Accession Numbers

CHEM002183
T3D2770

Identification

Common Name

Trihexyphenidyl

Class

Small Molecule

Description

Trihexyphenidyl is an exogenous organic compound with the formula C20H31NO and an average molecular weight of 301.47 g/mol. It exists as a solid at room temperature. Trihexyphenidyl belongs to the amines, a subclass of organonitrogen compounds within the organic compounds. The compound is associated with seven recorded sources, including healthcare, pharmaceuticals, and veterinary products as anticholinergic agents; household cleaning and consumer products such as cigar cigarettes, tobacco smoke filters, other smoking requisites, and non-electric simulated smoking devices; electrically stimulated smoking devices within electrical and electronic equipment; and food preservation in food, food processing, and cookware. The recorded route of exposure is oral. Trihexyphenidyl interacts with six recorded protein targets. It is a selective M1 muscarinic acetylcholine receptor (CHRM1) antagonist capable of discriminating between the M1 (cortical or neuronal) and peripheral muscarinic subtypes, such as cardiac and glandular. In the central nervous system, it partially blocks cholinergic activity responsible for the symptoms of Parkinson's disease and is thought to increase the availability of dopamine, which is critical for the initiation and smooth control of voluntary muscle movement. Additionally, trihexyphenidyl acts as an agonist of the muscarinic acetylcholine receptors M2 (CHRM2), M3 (CHRM3), M4 (CHRM4), and M5 (CHRM5), as well as one other protein.

Contaminant Type

Amine
Antidyskinetic
Antiparkinson Agent
Drug
Metabolite
Muscarinic Antagonist
Organic Compound
Synthetic Compound

Chemical Structure

MOL SDF PDB SMILES InChI

Synonyms

Value	Source
Apo-trihex	Kegg
Trihexylphenidyl	HMDB
Trihexylphenidyle	HMDB
Trihexylphenizyl	HMDB
Trihexyphenidyle	HMDB
Triphenidyl	HMDB
AHP brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
ApoTrihex	MeSH, HMDB
Eisai brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Hipokinon	MeSH, HMDB
Parkopan	MeSH, HMDB
Trihexyphenidyl hydrochloride	MeSH, HMDB
Trihexyphenidyl wyeth brand	MeSH, HMDB
apo Trihex	MeSH, HMDB
Artane	MeSH, HMDB
Benzhexol	MeSH, HMDB
Cypress brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Lederle brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Parkinane	MeSH, HMDB
Psicofarma brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Rugby brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Trihexidyl hydrochloride	MeSH, HMDB
Wyeth brand OF trihexyphenidyl	MeSH, HMDB
Wyeth brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Apotex brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Aventis brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Schrein brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Cyclodol	MeSH, HMDB
Hexal brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Liquipharm brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Pharmaceutical associates brand OF trihexyphenidyl hydrochloride	MeSH, HMDB
Trihexane	MeSH, HMDB
Trihexyphenidyl hydrochloride elixir	MeSH, HMDB

Chemical Formula

C₂₀H₃₁NO

Average Molecular Mass

301.466 g/mol

Monoisotopic Mass

301.241 g/mol

CAS Registry Number

144-11-6

IUPAC Name

1-cyclohexyl-1-phenyl-3-(piperidin-1-yl)propan-1-ol

Traditional Name

trihexyphenidyl

SMILES

OC(CCN1CCCCC1)(C1CCCCC1)C1=CC=CC=C1

InChI Identifier

InChI=1S/C20H31NO/c22-20(18-10-4-1-5-11-18,19-12-6-2-7-13-19)14-17-21-15-8-3-9-16-21/h1,4-5,10-11,19,22H,2-3,6-9,12-17H2

InChI Key

HWHLPVGTWGOCJO-UHFFFAOYSA-N

Chemical Taxonomy

Description

Belongs to the class of organic compounds known as aralkylamines. These are alkylamines in which the alkyl group is substituted at one carbon atom by an aromatic hydrocarbyl group.

Kingdom

Organic compounds

Super Class

Organic nitrogen compounds

Class

Organonitrogen compounds

Sub Class

Amines

Direct Parent

Aralkylamines

Alternative Parents

Substituents

Aralkylamine
Monocyclic benzene moiety
Piperidine
Benzenoid
1,3-aminoalcohol
Tertiary alcohol
Tertiary amine
Tertiary aliphatic amine
Azacycle
Organoheterocyclic compound
Alcohol
Organic oxygen compound
Hydrocarbon derivative
Organooxygen compound
Organopnictogen compound
Aromatic alcohol
Aromatic heteromonocyclic compound

Molecular Framework

Aromatic heteromonocyclic compounds

External Descriptors

amine (CHEBI:9720 )

Biological Properties

Status

Detected and Not Quantified

Origin

Exogenous

Cellular Locations

Membrane

Biofluid Locations

Not Available

Tissue Locations

Not Available

Applications

Not Available

Biological Roles

cholinergic antagonist (PMC6664820 )?
muscarinic antagonist (PMC6325674 )?
antagonist (PMC6664820 )?Substance that attaches to and blocks cell receptors that normally bind naturally occurring substances.

Chemical Roles

Not Available

Organoleptic Effects

Not Available

Physical Properties

State

Solid

Appearance

White powder.

Experimental Properties

Property	Value
Melting Point	258.5°C
Boiling Point	Not Available
Solubility	3.14e-03 g/L

Predicted Properties

Property	Value	Source
Water Solubility	0.0031 g/L	ALOGPS
logP	4.93	ALOGPS
logP	4.23	ChemAxon
logS	-5	ALOGPS
pKa (Strongest Acidic)	13.84	ChemAxon
pKa (Strongest Basic)	9.32	ChemAxon
Physiological Charge	1	ChemAxon
Hydrogen Acceptor Count	2	ChemAxon
Hydrogen Donor Count	1	ChemAxon
Polar Surface Area	23.47 Å²	ChemAxon
Rotatable Bond Count	5	ChemAxon
Refractivity	93.21 m³·mol⁻¹	ChemAxon
Polarizability	36.73 Å³	ChemAxon
Number of Rings	3	ChemAxon
Bioavailability	Yes	ChemAxon
Rule of Five	Yes	ChemAxon
Ghose Filter	Yes	ChemAxon
Veber's Rule	Yes	ChemAxon
MDDR-like Rule	No	ChemAxon

Spectra

Spectrum Type	Description	Splash Key	Deposition Date	View
Predicted GC-MS	Predicted GC-MS Spectrum	splash10-0a4j-9520000000-9a2c379908fc40e03fe2	Not Available	View Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum	splash10-08gm-8291000000-e91e4f7026454f2df547	Not Available	View Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum	Not Available	Not Available	View Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum	Not Available	Not Available	View Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum	Not Available	Not Available	View Spectrum
LC-MS/MS	LC-MS/MS Spectrum	splash10-0udi-4119000000-9ed82688d3c1b39f26eb	Not Available	View Spectrum
LC-MS/MS	LC-MS/MS Spectrum	splash10-00di-1190000000-eb1d6e20e193aabe8331	Not Available	View Spectrum
LC-MS/MS	LC-MS/MS Spectrum	splash10-004r-9440000000-9b8665d040c0679d223d	Not Available	View Spectrum
LC-MS/MS	LC-MS/MS Spectrum	splash10-009i-6950000000-12b0f3e5468353070296	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0f89-1096000000-d3df91688ef1945d673e	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0002-9130000000-5c5ffd9794999341adec	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-05mn-9210000000-f0b1224b58d81bff09de	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0udi-0019000000-7ed6535dacec03b4f64e	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0f89-9145000000-5ef99bbb769978df62bd	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-001i-9010000000-ee7ed12c77da3bd0134f	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0udi-3009000000-cd1bde8ffe3dde655051	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0002-9001000000-edf90121115e0df0494d	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0002-9020000000-c9173163c6667307ea2f	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0udi-0009000000-2b5232fe5f3af3692a07	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0udi-0319000000-5b77372872ee2d4b2758	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-0002-0390000000-a4123a20c113e31a331f	Not Available	View Spectrum
MS	MS Spectrum	splash10-0002-9200000000-2092a098302f5e63b76c	Not Available	View Spectrum

Toxicity Profile

Toxicity Values

Toxicity Value	Organism	Dose Descriptor	Route of Exposure	Predicted or Experimental	Toxicity Rating	Reference
885.0 Log mg/kg [500:1600]	Rat	LD50	oral	predicted	Not Available	Not Available
10.0 mg/kg-day	Rat	NOEL	injection	experimental	Not Available	ECOTOX - EPA ORD
10.0 mg/kg-day	Rat	LOEL	injection	experimental	Not Available	ECOTOX - EPA ORD

Toxicity / Toxin Class

Not Available

Mechanism of Toxicity

Trihexyphenidyl is a selective M1 muscarinic acetylcholine receptor antagonist. It is able to discriminate between the M1 (cortical or neuronal) and the peripheral muscarinic subtypes (cardiac and glandular). Trihexyphenidyl partially blocks cholinergic activity in the CNS, which is responsible for the symptoms of Parkinson's disease. It is also thought to increase the availability of dopamine, a brain chemical that is critical in the initiation and smooth control of voluntary muscle movement.

Carcinogenicity (IARC Classification)

No indication of carcinogenicity to humans (not listed by IARC).

Minimum Risk Level

Not Available

Symptoms

Symptoms of overdose include mydriasis, dryness of mucous membranes, red face, atonic states of bowels and bladder, and hyperthermia in high doses. Central consequences are agitation, confusion, and hallucinations.

Treatment

Treatment of acute overdose involves symptomatic and supportive therapy. Gastric lavage or other methods to limit absorption should be instituted. A small dose of diazepam or a short-acting barbiturate may be administered if CNS excitation is observed. Phenothiazines are contraindicated because the toxicity may be intensified due to their antimuscarinic action, causing coma. Respiratory support, artificial respiration or vasopressor agents may be necessary. Hyperpyrexia must be reversed, fluid volume replaced and acid-balance maintained. Urinary catheterization may be necessary. It is not known if Trihexyphenidyl is dialyzable. (2)

Health Effects

Health Effect	Relationship	Direction	Description	Reference
Parkinson's disease	Not Available	Not Available	A long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms generally come on slowly over time.	PMC6325674

Exposure Sources

Source ID	Source	Sector	Reference
CEDs000010	Insecticides?Insecticides are synthetic chemicals designed to control or eliminate insect pests that threaten crops and other agricultural products.	Agriculture & land management	PubChem
CEDs000372	Anticholinergic agents?Anticholinergic agents are a class of synthetic chemicals that inhibit the action of acetylcholine, a neurotransmitter involved in various physiological functions.	Healthcare, pharmaceuticals & veterinary products	Not Available
CEDs000518	Electrically Stimulated Smoking Devices?Electrically stimulated smoking devices, commonly known as e-cigarettes or vape pens, utilize electrical components to heat a liquid solution, often containing nicotine, flavorings, and other additives, to produce an aerosol for inhalation.	Electrical & Electronic Equipment	PubChem
CEDs000545	Food Preservation?Food preservation often involves the use of synthetic chemicals, such as preservatives, flavor enhancers, and color additives, to extend shelf life and enhance the sensory qualities of food products.	Food, food processing & cookware	PubChem
CEDs000556	Cigar Cigarettes?Cigar cigarettes are a source of synthetic chemical contamination due to the combustion of various tobacco blends and additives.	Household cleaning & consumer products	PubChem
CEDs000559	Non Electric Simulated Smoking Devices?Non-electric simulated smoking devices, often designed to mimic the experience of smoking without combustion, can be sources of synthetic chemical contamination due to the materials and chemicals used in their construction and operation.	Household cleaning & consumer products	PubChem
CEDs000560	Other Smoking Requisites?Other smoking requisites, including items such as lighters, matches, and rolling papers, can introduce synthetic chemical contamination through various components and additives.	Household cleaning & consumer products	PubChem
CEDs000569	Tobacco Smoke Filters?Tobacco smoke filters are designed to reduce the inhalation of harmful substances in cigarette smoke, including tar and other particulate matter.	Household cleaning & consumer products	PubChem
CEDs000580	Manufacture Preparation Of Tobacco Products?The manufacture and preparation of tobacco products involve various processes that can result in the introduction of synthetic chemicals into the environment.	Industrial manufacturing & chemical processing	PubChem
CEDs000609	Aftershave?Aftershave is a grooming product typically used to soothe and protect the skin following shaving.	Personal care & cosmetics	PubChem
CEDs000610	Aftersun Products?Aftersun products are designed to soothe and hydrate the skin after sun exposure, often containing various synthetic chemicals such as emollients, preservatives, and fragrances.	Personal care & cosmetics	PubChem
CEDs000611	Anti Perspirants Or Body Deoderants?Antiperspirants and body deodorants commonly contain synthetic chemicals such as aluminum compounds, parabens, and synthetic fragrances.	Personal care & cosmetics	PubChem
CEDs000614	Essential Oils Or Perfumes?Essential oils and perfumes are complex mixtures of volatile compounds derived from natural or synthetic sources, commonly used for their aromatic properties.	Personal care & cosmetics	PubChem
CEDs000615	Eye Makeup Products?Eye makeup products, including mascaras, eyeliners, and eyeshadows, often contain a variety of synthetic chemicals such as pigments, preservatives, and film-forming agents.	Personal care & cosmetics	PubChem
CEDs000617	Lip Care Products?Lip care products, including lipsticks, balms, and glosses, often contain a variety of synthetic chemicals such as parabens, phthalates, and synthetic fragrances.	Personal care & cosmetics	PubChem
CEDs000618	Lip Makeup Products?Lip makeup products, such as lipsticks, lip glosses, and lip liners, often contain a variety of synthetic chemicals, including pigments, preservatives, and emollients.	Personal care & cosmetics	PubChem
CEDs000642	Footwear?Footwear production often involves the use of various synthetic chemicals, such as adhesives, dyes, and treatments, which can contribute to environmental contamination.	Textiles, leather & furnishings	PubChem
CEDs000671	Airplanes And Helicopters?Airplanes and helicopters are significant sources of synthetic chemical contamination primarily through the use of aviation fuels, lubricants, and de-icing agents.	Aviation & Aerospace	PubChem
CEDs000685	Ceramics?Ceramics can be a source of synthetic chemical contamination through various additives and processing agents used in their production.	Building & Construction	PubChem
CEDs000696	Nanotechnology?Nanotechnology involves the manipulation of materials at the molecular or atomic level, typically within the range of 1 to 100 nanometers.	Industrial manufacturing & chemical processing	PubChem
CEDs000735	Explosives?Explosives are chemical compounds or mixtures designed to undergo rapid decomposition, releasing energy in the form of gas and heat.	Defense & military infrastructure	PubChem
CEDs000741	Pigment Pastes?Pigment pastes are concentrated dispersions of pigments used to impart color and properties to materials.	Paper, pulp & fiber products	PubChem
CEDs000744	Water, Wastewater, & Sewage Treatment?Water, wastewater, and sewage treatment processes are critical for managing and mitigating pollutants in water systems.	Wastewater, sanitation & biosolids	PubChem

Pathways

2 pathwaysPathway Source: PathBank

Trihexyphenidyl Action Pathway

Trihexyphenidyl Drug Metabolism Action Pathway

Targets

Structure	Protein	UniProt ID	Organism	Relationship	Details
Click to view 3D structure	Sigma non-opioid intracellular receptor 1	Q99720	Humans	Predicted (SEA)	Prediction Confidence Score 0.388 Applicability Domain 0.561 Statistical Significance 0.0146 Supporting Reference Compounds 562 E-value 113.893
Click to view 3D structure	Alpha-1B adrenergic receptor	P15823	Rattus norvegicus	Predicted (SEA)	Prediction Confidence Score 0.379 Applicability Domain 0.561 Statistical Significance 0.003 Supporting Reference Compounds 130 E-value 23.0434
Click to view 3D structure	D(2) dopamine receptor	P14416	Humans	Predicted (SEA)	Prediction Confidence Score 0.379 Applicability Domain 0.561 Statistical Significance 0.0268 Supporting Reference Compounds 1103 E-value 208.947
Click to view 3D structure	D(3) dopamine receptor	P35462	Humans	Predicted (SEA)	Prediction Confidence Score 0.378 Applicability Domain 0.561 Statistical Significance 0.0201 Supporting Reference Compounds 861 E-value 156.788
Click to view 3D structure	Muscarinic acetylcholine receptor M1	P11229	Humans	Predicted (SEA)	Prediction Confidence Score 0.378 Applicability Domain 0.561 Statistical Significance 0.0051 Supporting Reference Compounds 385 E-value 39.5474
Click to view 3D structure	Sigma non-opioid intracellular receptor 1	Q60492	Cavia porcellus	Predicted (SEA)	Prediction Confidence Score 0.372 Applicability Domain 0.425 Statistical Significance 0.0108 Supporting Reference Compounds 229 E-value 83.8436
Click to view 3D structure	5-hydroxytryptamine receptor 2A	P28223	Humans	Predicted (SEA)	Prediction Confidence Score 0.37 Applicability Domain 0.561 Statistical Significance 0.0263 Supporting Reference Compounds 955 E-value 204.977
Click to view 3D structure	Histamine H3 receptor	Q9Y5N1	Humans	Predicted (SEA)	Prediction Confidence Score 0.369 Applicability Domain 0.383 Statistical Significance 0.0084 Supporting Reference Compounds 294 E-value 65.2376
Click to view 3D structure	Muscarinic acetylcholine receptor M2	P08172	Humans	Predicted (SEA)	Prediction Confidence Score 0.363 Applicability Domain 0.561 Statistical Significance 0.0052 Supporting Reference Compounds 373 E-value 40.1702
Click to view 3D structure	Muscarinic acetylcholine receptor M3	P20309	Humans	Predicted (SEA)	Prediction Confidence Score 0.363 Applicability Domain 0.561 Statistical Significance 0.0044 Supporting Reference Compounds 310 E-value 34.3315
Click to view 3D structure	Muscarinic acetylcholine receptor M4	P08173	Humans	Predicted (SEA)	Prediction Confidence Score 0.363 Applicability Domain 0.561 Statistical Significance 0.004 Supporting Reference Compounds 297 E-value 31.4511
Click to view 3D structure	Muscarinic acetylcholine receptor M5	P08912	Humans	Predicted (SEA)	Prediction Confidence Score 0.359 Applicability Domain 0.561 Statistical Significance 0.0038 Supporting Reference Compounds 266 E-value 29.7384
Click to view 3D structure	Voltage-gated inwardly rectifying potassium channel KCNH2	Q12809	Humans	Predicted (SEA)	Prediction Confidence Score 0.355 Applicability Domain 0.383 Statistical Significance 0.0589 Supporting Reference Compounds 1498 E-value 458.532
Click to view 3D structure	Histamine H1 receptor	P35367	Humans	Predicted (SEA)	Prediction Confidence Score 0.346 Applicability Domain 0.383 Statistical Significance 0.0206 Supporting Reference Compounds 507 E-value 160.058
Click to view 3D structure	Cytochrome P450 2D6	P10635	Humans	Predicted (SEA)	Prediction Confidence Score 0.343 Applicability Domain 0.561 Statistical Significance 0.0383 Supporting Reference Compounds 1130 E-value 298.396
Click to view 3D structure	Sigma intracellular receptor 2	Q5U3Y7	Rattus norvegicus	Predicted (SEA)	Prediction Confidence Score 0.34 Applicability Domain 0.383 Statistical Significance 0.009 Supporting Reference Compounds 110 E-value 69.8307
Click to view 3D structure	Histamine H1 receptor	P31389	Cavia porcellus	Predicted (SEA)	Prediction Confidence Score 0.333 Applicability Domain 0.368 Statistical Significance 0.0076 Supporting Reference Compounds 101 E-value 59.399
Click to view 3D structure	Sigma non-opioid intracellular receptor 1	Q9R0C9	Rattus norvegicus	Predicted (SEA)	Prediction Confidence Score 0.333 Applicability Domain 0.425 Statistical Significance 0.0109 Supporting Reference Compounds 207 E-value 84.8557
Click to view 3D structure	5-hydroxytryptamine receptor 2B	P41595	Humans	Predicted (SEA)	Prediction Confidence Score 0.323 Applicability Domain 0.368 Statistical Significance 0.0312 Supporting Reference Compounds 686 E-value 243.279
Click to view 3D structure	Sodium-dependent dopamine transporter	Q01959	Humans	Predicted (SEA)	Prediction Confidence Score 0.321 Applicability Domain 0.368 Statistical Significance 0.0247 Supporting Reference Compounds 506 E-value 192.054
Click to view 3D structure	Histamine H2 receptor	P25021	Humans	Predicted (SEA)	Prediction Confidence Score 0.317 Applicability Domain 0.383 Statistical Significance 0.0138 Supporting Reference Compounds 256 E-value 107.821
Click to view 3D structure	Histamine H3 receptor	Q9QYN8	Rattus norvegicus	Predicted (SEA)	Prediction Confidence Score 0.316 Applicability Domain 0.34 Statistical Significance 0.0066 Supporting Reference Compounds 80 E-value 51.7697
Click to view 3D structure	Sodium-dependent noradrenaline transporter	P23975	Humans	Predicted (SEA)	Prediction Confidence Score 0.315 Applicability Domain 0.368 Statistical Significance 0.0261 Supporting Reference Compounds 451 E-value 203.109
Click to view 3D structure	Muscarinic acetylcholine receptor M2	P10980	Rattus norvegicus	Predicted (SEA)	Prediction Confidence Score 0.315 Applicability Domain 0.339 Statistical Significance 0.0034 Supporting Reference Compounds 98 E-value 26.7023
Click to view 3D structure	Alpha-2C adrenergic receptor	P18825	Humans	Predicted (SEA)	Prediction Confidence Score 0.314 Applicability Domain 0.368 Statistical Significance 0.0225 Supporting Reference Compounds 386 E-value 175.083
Click to view 3D structure	Muscarinic acetylcholine receptor M2	P08172	Humans	Known	Not Available
Click to view 3D structure	Muscarinic acetylcholine receptor M3	P20309	Humans	Known	Not Available
Click to view 3D structure	Muscarinic acetylcholine receptor M1	P11229	Humans	Known	Trihexyphenidyl is a selective M1 muscarinic acetylcholine receptor antagonist. It is able to discriminate between the M1 (cortical or neuronal) and the peripheral muscarinic subtypes (cardiac and glandular). Trihexyphenidyl partially blocks cholinergic activity in the CNS, which is responsible for the symptoms of Parkinson's disease. It is also thought to increase the availability of dopamine, a brain chemical that is critical in the initiation and smooth control of voluntary muscle movement.
Click to view 3D structure	Muscarinic acetylcholine receptor M4	P08173	Humans	Known	Not Available
Click to view 3D structure	Muscarinic acetylcholine receptor M5	P08912	Humans	Known	Not Available