Psilocin

Effects

Shulgin notes

These figures come from the Shulgins' own small trials, published decades ago. They are history, not a dosing guide: they were never checked the way a harm reduction dose table is, and batches, purity and people differ.

Book

TiHKAL (1997), entry #18

Dose listed

10–20 mg orally WP

Duration listed

3–6 hours WP

Read entry #18 in Erowid's online library

From PiHKAL and TiHKAL by Alexander and Ann Shulgin, as tabulated in Wikipedia's articles on the books (CC BY-SA 4.0). The books' text belongs to the Shulgins, so only the listed figures and a link are given here. Synthesis details are never shown on this site.

Overview

4-Hydroxy-N,N-dimethyltryptamine (also known as 4-HO-DMT, 4-OH-DMT, and psilocin) is a naturally-occurring psychedelic substance of the tryptamine class. Psilocin is the primary psychoactive constituent in certain species of mushrooms, and as a closely related structural analog of the powerful visionary entheogen DMT (also known as N,N-dimethyltryptamine). PW

Psilocin is a substutued tryptamine alkaloid, that is present in most psychedelic mushrooms. It is relatively unstable in solution due to the -OH group. TS

Psilocin, also known as 4-hydroxy-N,N-dimethyltryptamine (4-HO-DMT), is a psychedelic drug and fungal alkaloid of the tryptamine and 4-hydroxytryptamine families. Along with its phosphate ester psilocybin, it is found in most species of psilocybin-containing mushrooms, such as Psilocybe cubensis and Psilocybe mexicana, and is the compound responsible for their hallucinogenic effects, although concentrations of psilocin are variably lower than those of psilocybin. The drug is taken orally and its effects include perceptual changes and visual effects, emotional changes, ego dissolution, time dilation, and mystical experiences, among others. Synthetic acyl esters such as 4-AcO-DMT (psilacetin; O-acetylpsilocin) and 4-PrO-DMT (O-propionylpsilocin), are prodrugs of psilocin and have similar properties and effects. More recently, MSP-1014 has emerged as a novel prodrug of psilocin under development for the treatment of major depressive disorder.[1–9] WP

Psilocin acts as a non-selective serotonin receptor agonist, including of the serotonin 5-HT2A receptor among others. The drug produces its hallucinogenic effects specifically via activation of the serotonin 5-HT2A receptor. However, other serotonin receptors, such as the serotonin 5-HT1A and 5-HT2C receptors, may also contribute to its effects. Notable analogues of psilocin include dimethyltryptamine (DMT), its positional isomer bufotenin (5-HO-DMT), its higher homologue 4-HO-MET (metocin), and others.[3][10–16] WP

Psilocin and psilocybin were discovered via isolation from psilocybin-containing mushrooms by Albert Hofmann in 1958. This followed the Western re-discovery of psilocybin-containing mushrooms by Robert Gordon Wasson and Valentina Pavlovna Wasson in Mexico in 1955. Psilocin, in the form of psilocybin, psilocybin-containing mushrooms, and other prodrugs such as 4-AcO-DMT, is a widely used entheogen as well as recreational psychedelic drug. Psilocybin and psilocin became controlled substances in the United States and internationally under the United Nations in 1971. Since then, psilocin, as the active form of psilocybin, has become of interest for potential use in medicine to treat psychiatric disorders such as depression. Psilocybin was approved for such purposes in Australia in 2023 and is in late-stage clinical trials in the United States and other countries.[1][17–27] WP

History

History

Psilocin and its phosphorylated cousin, psilocybin, were first isolated and named in 1958 by Swiss chemist Albert Hofmann. He obtained the chemicals from laboratory-grown specimens of the hallucinogenic mushroom Psilocybe mexicana. Hofmann also succeeded in finding synthetic routes to these chemicals.[1][17][28] WP

Legal status

• Psilocin is a Schedule I drug under the Convention on Psychotropic Substances, meaning the possession and sale of it (including psilocin and psilocybin-containing mushrooms) is prohibited in most countries.[29] PW
• Belgium: Possession and sale of mushrooms have been illegal since 1988. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Brazil: Possession, production and sale is illegal as it is listed on Portaria SVS/MS nº 344, but mushrooms fall under religious use laws.[30] PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• British Virgin Isles: The sale of mushrooms is illegal, but possession and consumption is legal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Bulgaria: The sale of mushrooms is illegal, but possession and consumption is legal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Canada: Psilocybin and psilocin are illegal to possess, obtain or produce without a prescription or license as they are Schedule III under the Controlled Drugs and Substances Act.[31] PW
• Cyprus The possession, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Czech Republic: The distribution (including sale) of mushrooms is illegal, but consumption is legal. The possession of over 40 hallucinogenic caps is considered a crime if they contain more than 50mg of psilocin or the corresponding amount of psilocybin. The possession of more than 40g of hallucinogenic mycelium is considered a crime. If these limits are not exceeded, the act is considered a minor offence and a fine of up to 15 thousand CZK may be imposed. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Denmark: The possession, growth, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Finland: The possession, growth, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Germany: Psilocin is controlled under Anlage I BtMG (Narcotics Act, Schedule I), former: Opiumgesetz (Opium Act) as of February 25, 1967. It is illegal to manufacture, possess, import, export, buy, sell, procure or dispense it without a license.[32][33][34] PW
• Greece: The possession, growth, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Ireland: The possession, growth, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Japan: The possession, growth, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Latvia: Hallucinogenic mushrooms, psilocin and psilocibyn are Schedule I controlled substances.[35] PW
• Mexico: The possession, growth, sale and consumption of mushrooms is illegal. Rules are relaxed regarding religious use however. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• The Netherlands: The possession, growth, sale and consumption of mushrooms is illegal. However, due to a legal loophole, psilocybin truffles can be legally possessed, grown, sold and consumed. PW
• New Zealand: Psilocybin is Class A. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Norway: Possession, growth, sale and consumption of mushrooms is illegal. Spores, even though not containing psilocybin, are also illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• Switzerland: Psilocin is a controlled substance specifically named under Verzeichnis D. Mushrooms of the species Conocybe, Panaeolus, Psilocybe and Stropharia are also controlled under Verzechnis D.[36] PW
• Turkey: The possession, growth, sale and consumption of mushrooms is illegal. PW⚠ PsychonautWiki itself has flagged this text: citation needed.
• United Kingdom: According to the 2005 Drugs Act, fresh and prepared psilocybin mushrooms are Class A.[37] PW
• United States: Psilocybin and psilocin are illegal Schedule I drugs.[38] PW

United nations

Psilocin is a Schedule I drug under the Convention on Psychotropic Substances. The United Nations Convention on Psychotropic Substances (adopted in 1971) requires its members to prohibit psilocybin, and parties to the treaty are required to restrict the use of the drug to medical and scientific research under strictly controlled conditions.[39] WP

Australia

Psilocin is considered a Schedule 9 prohibited substance in Australia under the Poisons Standard (October 2015). A Schedule 9 substance is a substance which may be abused or misused, the manufacture, possession, sale or use of which should be prohibited by law except when required for medical or scientific research, or for analytical, teaching or training purposes with approval of Commonwealth and/or State or Territory Health Authorities.[40] WP

Canada

Psilocin is a Schedule III controlled substance in Canada.[41] WP

Russia

Psilocin and psilocybin are banned in Russia, due to their status as narcotic drugs, with a criminal penalty for possession of more than 50 mg.[42] WP

United states

Psilocin is a Schedule I controlled substance in the United States since 1971.[20] WP

Pharmacology

Pharmacodynamics

Psilocin is the pharmacologically active agent in the body after ingestion of psilocybin or some species of psychedelic mushrooms. Psilocybin is rapidly dephosphorylated in the body to psilocin which acts as a serotonin 5-HT2A, 5-HT2C and 5-HT1A receptor agonist or partial agonist. Psilocin exhibits functional selectivity in that it activates phospholipase A2 instead of activating phospholipase C as the endogenous ligand serotonin does. Psilocin is structurally similar to serotonin (5-hydroxytryptamine), differing only by the hydroxyl group being on the 4-position rather than the 5 and the dimethyl groups on the nitrogen. Its effects are thought to come from its agonist activity at 5-HT2A receptors in the prefrontal cortex. Psilocin's psychedelic effects are directly correlated with the drug's occupancy at these receptor sites. The drug shows pronounced biased agonism at the serotonin 5-HT2C receptor. Psilocin has no significant effect on dopamine receptors and only affects the noradrenergic system at very high doses.[43–46] WP

Psilocin has been reported to act as a highly potent positive allosteric modulator of the tropomyosin receptor kinase B (TrkB), one of the receptors of brain-derived neurotrophic factor (BDNF). However, subsequent studies failed to reproduce these findings and instead found no interaction of psilocin with TrkB.[10][18][47][48] WP

The cryo-EM structures of the serotonin 5-HT2A receptor with psilocin, as well as with various other psychedelics and serotonin 5-HT2A receptor agonists, have been solved and published by Bryan L. Roth and colleagues.[49][50] WP

Pharmacokinetics

Psilocin's elimination half-life ranges from 1 to 3 hours depending on route of administration of psilocybin.[4] WP

Chemistry

Formula

C12H16N2O PC

CAS number

520-53-6 PC

Molar mass (g/mol)

204.27 PC

IUPAC name (computed by PubChem)

3-[2-(dimethylamino)ethyl]-1H-indol-4-ol PC

SMILES

CN(C)CCC1=CNC2=C1C(=CC=C2)O PC

InChIKey

SPCIYGNTAMCTRO-UHFFFAOYSA-N PC

PubChem CID

4980

Pop culture

No references added yet.

References

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29. Other List of Psychotropic Substances under International Control (Green List)
30. Other RESOLUÇÃO DA DIRETORIA COLEGIADA - RDC N° 130, DE 2 DE DEZEMBRO DE 2016
31. Other Schedule III
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33. Other Vierte Verordnung über die den Betäubungsmitteln gleichgestellten Stoffe
34. Other Gesetz über den Verkehr mit Betäubungsmitteln: § 29
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