Psilocin: Compound Guide

Urgent first. For poisoning or a medical emergency after eating a mushroom or product, call 911 or US Poison Help at 1-800-222-1222. For a mental health crisis in the US, call or text 988.

This page is education only: no amounts, no sourcing, no preparation. It explains one compound and how it differs from psilocybin.

What psilocin is

Psilocin is the pharmacologically active substance the body makes from psilocybin. Psilocybin is a prodrug, dephosphorylated by the enzyme alkaline phosphatase into psilocin. [1] NIDA says psilocin attaches to and activates serotonin receptors, primarily the 5-HT2A receptor, and that researchers think this action is responsible for much of the subjective experience. [2]

Psilocybin vs psilocin

Both occur in fungi: psilocybin and psilocin, with related compounds, typically occur in most species of the genus Psilocybe. [3] For the full guide to the parent compound see psilocybin; for a side-by-side see psilocybin vs psilocin.

What is known about how psilocin moves through the body

A systematic review of 19 publications (12 unique datasets) found that after oral psilocybin, psilocin appears quickly, with a terminal half-life across studies of 1.23 to 4.72 hours, and that only 1.5 to 3.4% of the dose is excreted as unchanged psilocin in urine. [4] These are results from clinical studies of psilocybin, not a guide to how any product will act. Metabolism also varies between people; a toxicology review reports considerable physiological variability that can influence response. [1] Psilocin-O-glucuronide is the main urinary metabolite relevant to diagnosis. [1]

What research shows

Evidence labels: promising but limited, insufficient evidence. Clinical trials give psilocybin, not psilocin, and psilocin is the active form it becomes. Trial results are on the psilocybin page: for example one randomized trial in major depression found a larger fall in depression scores than placebo, with more adverse events. [5] We found no trials that give psilocin itself as the study drug in the sources read; Proper evidence not found for psilocin as a separate treatment (checked PubMed pharmacokinetics and clinical reviews). See psychedelics for major depressive disorder.

Risks

Risks follow those of psilocybin: raised blood pressure and heart rate, nausea, anxiety and, outside supervised settings, dangerous behavior. [2] A meta-analysis of therapeutic-dose trials found headache, nausea, anxiety, dizziness and raised blood pressure were more common than with comparison treatments. [6] No safety data in pregnancy exist per NIDA. [2] See psychedelic adverse effects and contraindications.

Quality and labeling

In a study of eight mushroom gummies sold in Portland, Oregon, seven contained psilocin and six contained 4-acetoxy-DMT, a related compound, and labeling was inaccurate in many. [7] Labels do not reliably tell you what a product contains.

Legal status

Not legal advice; laws change. In the United States, "psilocyn" (psilocin) is listed in Schedule I in 21 CFR 1308.11 (eCFR, read 2026-10-22). [8] Other countries: not verified. See psychedelic legal status.