Start Here

Pillars

Practice — how to do it Science — research The Root — origin & lineage Member Stories — first-person What We Reject — our lines The Mycelium — news
Browse Everything FAQ Dictionary Manifesto
Connect Contact

The Science

Psilocybin vs Psilocin: The Active Compound, Explained

Psilocybin and psilocin are two different molecules. One is in the mushroom. The other is what your body actually responds to. Here is how the conversion works and why it matters.

By The Microdose Movement ·

In one sentence: Psilocybin is the molecule in the mushroom; psilocin is what your body turns it into, and psilocin is the active compound that actually crosses into the brain.

People use the words psilocybin and psilocin interchangeably, but they are two different molecules with two different jobs. Understanding which is which makes the rest of the science easier to follow — including dosing, onset times, drug interactions, and why exact comparisons between mushroom strains can be misleading.

This page explains the chemistry, the metabolism, and what it actually means in practice for someone taking a microdose.

What is psilocybin?

Psilocybin is the compound mushrooms produce. It is found in over 200 species of fungi, most prominently in Psilocybe cubensis and its relatives. Chemically, it is 4-phosphoryloxy-N,N-dimethyltryptamine — an indole alkaloid in the tryptamine family, structurally similar to the neurotransmitter serotonin.

The Swiss chemist Albert Hofmann isolated psilocybin from Psilocybe mexicana in 1958 and synthesized it in his lab in 1959. Hofmann was the same chemist who first synthesized LSD in 1938. Psilocybin was sold legally by Sandoz Pharmaceuticals under the brand name Indocybin for psychiatric research throughout the 1960s, until the Controlled Substances Act ended that work in 1970.

Psilocybin itself is essentially a pharmacological prodrug. It is not the molecule that produces the psychedelic experience. When you take psilocybin into your body, very little of it reaches your brain in its original form. The molecule has to be converted first.

What is psilocin?

Psilocin is what psilocybin becomes after your body strips one chemical group from it. Specifically, an enzyme called alkaline phosphatase — present in your gut, liver, kidneys, and blood — removes the phosphate group from psilocybin. The result is 4-hydroxy-N,N-dimethyltryptamine, also called psilocin.

Without that phosphate group, the molecule is small enough and lipid-soluble enough to cross the blood-brain barrier. Once it crosses, it binds to the 5-HT2A serotonin receptor and begins the cascade of effects that produce the psychedelic experience.

In other words: psilocybin is the storage form. Psilocin is the active form.

This is similar to how some pharmaceutical drugs work. Codeine, for example, is a prodrug that the liver converts to morphine. The drug you swallow is not the drug that does the work.

How quickly does psilocybin convert to psilocin?

Conversion begins in the stomach almost immediately and is largely complete within an hour. Most pharmacokinetic studies show:

These numbers come from formal pharmacokinetic studies, the most rigorous of which is the 2017 work by Hasler and colleagues at the University of Zurich. The variability between individuals is significant — some people convert faster, some slower, and stomach contents affect everything. Microdosing on an empty stomach generally produces a slightly faster onset and a more reliable subjective profile than dosing after a meal.

Does taking psilocin directly work differently than psilocybin?

Slightly, but the difference is mostly in the onset, not the experience itself.

Psilocin is the active molecule, so taking pure psilocin directly skips the conversion step. The onset is faster — sometimes within 10–15 minutes — and the duration is somewhat shorter because the body is starting from a smaller initial dose of the active compound and metabolizing it on a steeper curve.

In practice, psilocin is much less stable than psilocybin. It oxidizes when exposed to air, light, or even mild heat, which is why mushroom material that has been improperly stored loses potency. Psilocybin is the more durable molecule, which is one reason mushrooms evolved to produce it in that form.

For most people taking dried mushroom material, this distinction is academic. You are eating psilocybin and your gut is making psilocin. The end result is the same.

Why does the conversion matter for dosing?

Three reasons.

First, it makes mushroom-to-mushroom comparison harder than people assume. Different Psilocybe species, and even different cultivated strains within Psilocybe cubensis, contain different ratios of psilocybin to psilocin. Some strains contain more psilocin already in the mushroom, which can produce a slightly different felt onset. The total active dose depends on both compounds combined.

Second, the conversion is one of the variables that explains individual response. People with different gut enzyme activity convert psilocybin to psilocin at slightly different rates. This is part of why two people taking the same dose can have noticeably different experiences.

Third, it explains some drug interactions. Compounds that affect alkaline phosphatase activity, gut motility, or liver enzyme function can change how much psilocin actually reaches your brain from a given dose of psilocybin. This is one mechanism behind some of the variability in SSRI and psilocybin combinations.

What happens after psilocin does its work?

Psilocin is broken down by the liver and excreted, primarily through the kidneys. The main metabolic route is glucuronidation — the liver attaches a sugar molecule to psilocin to make it water-soluble enough for the kidneys to filter out. Most of a psilocin dose has been metabolized within 24 hours, and standard urine drug screens do not detect it after about 2–3 days.

Specialized lab tests can detect psilocin in hair samples for longer periods, but these tests are rare and not part of standard drug screening panels.

What we still do not know about psilocybin metabolism

Frequently Asked Questions

Are psilocybin and psilocin the same thing?

No. Psilocybin is the molecule found in the mushroom. Psilocin is the molecule your body produces by removing a phosphate group from psilocybin. Psilocin is the form that actually crosses the blood-brain barrier and produces the psychedelic effect.

Why does the body convert psilocybin to psilocin?

Psilocybin is too polar to cross the blood-brain barrier easily. Removing the phosphate group makes the molecule smaller and more lipid-soluble, which lets it enter the brain. The conversion happens via the enzyme alkaline phosphatase, which is widely distributed in the body.

How long does psilocin stay in your system?

Psilocin has a plasma half-life of about 3 hours, which means most of a dose has been metabolized within 12–18 hours. Detectable traces clear from urine within 2–3 days. The subjective effects are gone within 4–6 hours of dosing.

Is psilocin stronger than psilocybin?

Per milligram, yes — psilocin is the active compound and psilocybin needs to be converted before it does anything. But because psilocybin reliably converts to psilocin in the body, taking psilocybin produces the same overall experience, just with a slightly slower onset.

Why do mushrooms contain psilocybin instead of psilocin?

Psilocybin is more stable than psilocin. Psilocin oxidizes quickly in air and light, which is why mushroom material loses potency when stored badly. Mushrooms evolved to produce the more stable storage form, and the conversion happens in the body of whatever animal consumes them.

Sources and Further Reading

This page is for educational purposes. Nothing here is medical advice. The Microdose Movement is an educational community, not a clinical provider.