What Is Psilocybin? The Compound Behind Magic Mushrooms

Psilocybin is the naturally occurring psychedelic compound found in “magic mushrooms”—more than 200 species of fungi, most in the genus Psilocybe. It's the molecule responsible for these mushrooms' famous effects, the reason they're federally controlled, and the focus of a growing wave of modern medical research. Here's a clear, science-based look at what psilocybin actually is.

Whether you're curious about the chemistry, the history, or where the law and research stand today, this guide breaks down psilocybin from a factual, educational perspective.

What Is Psilocybin?

Psilocybin is a naturally occurring psychedelic compound produced by certain mushrooms. Chemically, it's a tryptamine—structurally related to the neurotransmitter serotonin—which is part of why it affects the brain the way it does. On its own, psilocybin is what scientists call a “prodrug”: once ingested, the body converts it into psilocin, the active form that interacts with serotonin receptors in the brain. Both psilocybin and psilocin are the compounds regulated under law.

Which Mushrooms Contain Psilocybin?

Psilocybin is found in over 200 species of mushrooms worldwide, the majority in the genus Psilocybe, along with some species in related genera like Panaeolus. The best-known is Psilocybe cubensis, the species behind the hundreds of named cultivated strains. These species share recognizable traits—most produce a purple-brown spore print and bruise blue where handled. You can explore the full range in our guide to the types of magic mushrooms.

How Was Psilocybin Discovered?

While Indigenous cultures in Mesoamerica used these mushrooms for centuries—famously the Mazatec healer María Sabina—psilocybin itself was first isolated in the laboratory in 1958 by the Swiss chemist Albert Hofmann (the same chemist who discovered LSD), working from Psilocybe mexicana. That isolation opened the door to decades of scientific study.

Is Psilocybin Legal?

In the United States, psilocybin and psilocin are Schedule I controlled substances under federal law. In recent years, however, the picture has been shifting: Oregon and Colorado have established state-regulated frameworks for supervised adult psilocybin use, and several cities have deprioritized enforcement. Importantly, mushroom spores occupy a different legal position, because they contain no psilocybin—which is why they can be sold for microscopy. For the full breakdown, see our guide: Are Magic Mushroom Spores Legal?

Psilocybin Research Today

Psilocybin is at the center of a resurgence in psychedelic science. Researchers at major universities are studying it in clinical trials for conditions like treatment-resistant depression, anxiety, and PTSD, and the FDA has granted it “breakthrough therapy” designation for some of this work. This research is ongoing and conducted under strict clinical conditions—but it's a major reason interest in these mushrooms has grown so rapidly.

Psilocybin & Spore Genetics

As a spore vendor, our focus is the science of these fungi—their genetics, taxonomy, and identification. The spores we supply contain no psilocybin and are sold strictly for microscopy and taxonomy research. If you're interested in studying psilocybin-producing species at the microscopic level, browse our mushroom spores collection.

Frequently Asked Questions

What is psilocybin?

Psilocybin is a naturally occurring psychedelic compound found in certain mushrooms. It's a tryptamine related to serotonin, and the body converts it into the active compound psilocin.

What's the difference between psilocybin and psilocin?

Psilocybin is the compound found in the mushroom; psilocin is the active form the body converts it into. Both are controlled substances.

Which mushrooms contain psilocybin?

Over 200 species, mostly in the genus Psilocybe (like Psilocybe cubensis), plus some in related genera such as Panaeolus.

Is psilocybin legal?

It's a Schedule I controlled substance federally, though Oregon and Colorado have created regulated adult-use frameworks. Mushroom spores are treated differently because they contain no psilocybin.

Who discovered psilocybin?

It was first isolated in 1958 by Swiss chemist Albert Hofmann, from Psilocybe mexicana—though the mushrooms had been used in Indigenous traditions for centuries.

Disclaimer: This article is for educational purposes only and is not medical or legal advice, nor encouragement to use a controlled substance. Psilocybin and psilocin are Schedule I substances under U.S. federal law. Spore Genetics sells spores strictly for microscopy and taxonomy research; spores contain no psilocybin.