muscimol

Also known as agarin, pantherine, 5-(aminomethyl)-3(2H)-isoxazolone

Muscimol, also known as agarin, pantherine, or pyroibotenic acid, is a GABAA receptor agonist with sedative and hallucinogenic effects and the principal psychoactive constituent of Amanita mushrooms such as Amanita muscaria (fly agaric) and Amanita pantherina (panther cap). It is a 3-hydroxyisoxazole alkaloid and is closely related structurally to the neurotransmitter γ-aminobutyric acid (GABA). The compound is widely used as a ligand and agonist of the GABAA receptor in scientific research. Muscimol is typically taken orally, but may also be smoked. Peak effects occur after 1 to 3hours orally

Key facts

Drug.Verifiedfields: verified
Drug.Watchedfields: verified
Drug.verifiedrevid: 410573320
Drug.image: Muscimol chemical structure.svg
Drug.image_class: skin-invert-image
Drug.width: 200px
Drug.image2: Muscimol structure ball and stick.png
Drug.image_class2: bg-transparent
Drug.width2: 185px
Drug.routes_of_administration: Oral, smoking
Drug.class: GABAA receptor agonist; Sedative; Hypnotic; Hallucinogen
Drug.ATC_prefix: None
Drug.legal_AU: S9
Drug.legal_status: SE: Under investigation Uncontrolled, in general
Drug.bioavailability: Unknown
Drug.protein_bound: Unknown
Drug.metabolism: Transamination (via GABA-T)
Drug.onset: 0.5–2 hours (peak 1–3 hours)

via Wikipedia infobox

Chemical data

Formula: C4H6N2O2
Molecular weight: 114.1 g/mol
IUPAC name: 5-(azaniumylmethyl)-1,2-oxazol-3-olate
SMILES: C1=C(ON=C1[O-])C[NH3+]
InChIKey: ZJQHPWUVQPJPQT-UHFFFAOYSA-N
XLogP: -0.1
Polar surface area: 76.7 Å²
H-bond donors: 1
H-bond acceptors: 3
Formal charge: 0

via PubChem

Research

7,020 papers

Classics in Chemical Neuroscience: Muscimol.ACS chemical neuroscience · 2024
Synthesis of [(3)H]muscimol.Journal of labelled compounds & radiopharmaceuticals · 2025
Muscimol as an ionotropic GABA receptor agonist.Neurochemical research · 2014
Psychoactive Isoxazoles, Muscimol, and Isoxazole Derivatives from the Amanita (Agaricomycetes) Species: Review of New Trends in Synthesis, Dosage, and Biological Properties.International journal of medicinal mushrooms · 2023
Muscimol inhibits plasma membrane rupture and ninjurin-1 oligomerization during pyroptosis.Communications biology · 2023

via PubMed

Wikidata facts

Mass: 114.042927

Show 4 more facts

chemical formula: C₄H₆N₂O₂
canonical SMILES: C1=C(ONC1=O)CN
Commons category: Muscimol
median lethal dose (LD50): 4.5

Sources (4)

via Wikidata · CC0

~20 min read

Article

27 sections

Contents

Natural occurrence
Use and effects
Toxicity and overdose
Interactions
Pharmacology
Pharmacodynamics
Pharmacokinetics
Absorption
Distribution
Metabolism
Elimination
Chemistry
Structure
Properties
Isolation
Synthesis
Analogues
History
Society and culture
Legal status
Australia
Poland
United States
Research
See also
References
External links

The effects of muscimol in humans include central depression, sedation, sleep, cognitive and motor impairment, hallucinations, perceptual distortion, and muscle twitching, among others. Muscimol acts as a potent GABAA receptor full agonist. It is also a potent GABAA-ρ receptor partial agonist and a weak GABA reuptake inhibitor. The drug is inactive at the GABAB receptor but is a substrate of GABA transaminase (GABA-T). Muscimol mostly exerts its effects via GABAA receptor activation. It is very different from drugs like benzodiazepines and barbiturates as it is an orthosteric agonist of the GABAA receptor rather than an allosteric modulator. Unlike GABA, muscimol crosses the blood–brain barrier and hence is centrally active. Muscimol, which is also known chemically as 5-aminomethylisoxazol-3-ol, is a conformationally restrained analogue of GABA. The related compound and Amanita spp. constituent ibotenic acid is a prodrug of muscimol.