A short history of psilocybin

Mesoamerica and the Florentine Codex

Long before psilocybin had a name, mushrooms containing it were sacred in Mesoamerica. The Aztecs called them teonanácatl, usually translated as "god's flesh," and used them in religious and healing rituals.¹ Around 1560, the Franciscan friar Bernardino de Sahagún described their use in the Florentine Codex, his encyclopedic account of Aztec life.^2,1 Spanish missionaries tried to stamp the practice out.¹ It survived in Indigenous communities in what is now Oaxaca, where outsiders would encounter it again four centuries later.

María Sabina, Gordon Wasson and LIFE

In 1955 the American banker and amateur mycologist R. Gordon Wasson took part in a velada, an all-night mushroom ceremony, led by the Mazatec healer María Sabina in Huautla de Jiménez, Oaxaca.^3,4 Researchers credit her as the first person to let Western scientists observe these ritual practices.³

On May 13, 1957, LIFE magazine published Wasson's photo-essay "Seeking the Magic Mushroom," the first popular media coverage of the mushrooms.^2,26 Wasson disguised Sabina's name in that article but later published it, and the attention brought a stream of outside visitors to Huautla. Accounts of her life describe how she was ostracized by members of her community afterward.⁴

Hofmann, Sandoz and Indocybin

The French mycologist Roger Heim described Psilocybe mexicana, grew it in Paris and sent dried material to Albert Hofmann at the Swiss drug company Sandoz, the chemist who'd discovered LSD.²⁹ In 1958 Hofmann and colleagues reported isolating psilocybin, and in 1959 they described the structure of psilocybin and psilocin and how to synthesize them.^5,6 Sandoz went on to market synthetic psilocybin as Indocybin for experimental and psychotherapeutic use,⁷ with pill production dating to about 1960.²

Harvard and the Good Friday Experiment

In 1960, Harvard psychologists Timothy Leary and Richard Alpert began the Harvard Psilocybin Project. Colleagues raised concerns about safety and methods, and by spring 1963 both men had been dismissed and the project ended.^8,2

The era's best-known experiment took place on Good Friday, April 20, 1962, at Boston University's Marsh Chapel. Walter Pahnke, a Harvard doctoral student, gave psilocybin to half of a group of 20 divinity students and an active placebo to the rest.¹⁰ When Rick Doblin tracked down 16 of the 20 participants 24 to 27 years later, those who'd received psilocybin still described lasting positive effects. Doblin also found that one psilocybin participant had been given an injected tranquilizer during the session, a fact Pahnke hadn't reported.⁹

Prohibition

The United States banned possession of psilocybin and psilocin on October 24, 1968.² The Controlled Substances Act, signed on October 27, 1970, placed both in Schedule I, the category for drugs with no accepted medical use, where they remain today.^2,12 The 1971 UN Convention on Psychotropic Substances listed psilocybin and psilocin internationally, but not the mushrooms themselves. In 2001 the International Narcotics Control Board's secretary confirmed that no plants or fungi containing them were controlled under the treaty, while noting that countries could still ban them under national law.^11,7

The research revival

In 2000, Johns Hopkins became the first group in the United States to win regulatory approval to restart research with psychedelics in healthy volunteers.¹³ Its 2006 study, led by Roland Griffiths, found that participants rated their psilocybin session as personally and spiritually significant two months later, and helped reopen the field.¹⁴

The FDA granted Breakthrough Therapy designation, a status meant to speed development of promising drugs, to COMPASS Pathways' psilocybin therapy for treatment-resistant depression in 2018¹⁵ and to the Usona Institute's psilocybin for major depressive disorder in November 2019.¹⁶ Two months earlier, in September 2019, Johns Hopkins had opened its Center for Psychedelic and Consciousness Research with $17 million in private funding.¹³ The studies that followed are on our research tracker.

Decriminalization and state programs

On May 7, 2019, Denver voters approved Initiative 301 by 50.6% to 49.4%, making adult psilocybin possession the city's lowest law enforcement priority. Denver became the first U.S. city to decriminalize psilocybin mushrooms.¹⁷ Oakland's city council followed on June 4 with a broader measure covering entheogenic plants and fungi.¹⁸

Oregon voters passed Measure 109 in November 2020, creating the first state-licensed psilocybin services program; the first licenses were issued in 2023. Colorado voters approved Proposition 122 in November 2022, creating a regulated natural medicine program.¹⁹ Where every state stands now is on our legal status map.

The drug-approval era

In April 2025, New Mexico enacted the Medical Psilocybin Act, creating a state medical psilocybin program for patients with qualifying conditions.²⁸ That June, Compass Pathways reported that its psilocybin drug, COMP360, beat placebo for treatment-resistant depression in a Phase 3 trial, the first of its two Phase 3 trials of the drug.²⁰ A second Phase 3 trial succeeded in February 2026,²¹ and on April 18, 2026, Executive Order 14401 directed federal agencies to speed review of promising psychedelic drugs.²² As of October 2026, no psilocybin drug has been approved. Where COMP360 stands.

Norway and Scandinavia

Scandinavia's psilocybin story is mostly the story of one wild species, the liberty cap, known in Norway as spiss fleinsopp. In 1981, researchers at the University of Oslo recorded that it "has been used as a narcotic drug in Norway," mapped where it grows and measured how much its psilocybin content varies.²³ Norway's narcotics regulation prohibits the mushrooms themselves, including their spores.²⁴ In neighboring Denmark, a 1992 survey from Aarhus suggested mushrooms were the most commonly used hallucinogen among young people, ahead of LSD.²⁷

Norwegian researchers have also shaped the modern debate. Teri Krebs, of the Norwegian University of Science and Technology, and Pål-Ørjan Johansen analyzed U.S. national survey data from more than 130,000 people and found no link between lifetime psychedelic use and mental health problems.²⁵ And from 2001 to about 2020, this domain was home to NorShroom, a Norwegian-language community built around the liberty cap. We're not connected to its original team; more on the domain's history.

Timeline

1. c. 1560: Sahagún describes Aztec use of teonanácatl in the Florentine Codex.²
2. 1955: R. Gordon Wasson attends a velada led by María Sabina in Huautla de Jiménez.³
3. May 13, 1957: LIFE publishes "Seeking the Magic Mushroom."²
4. 1958: Albert Hofmann and colleagues isolate psilocybin.⁵
5. 1960: The Harvard Psilocybin Project begins.⁸
6. April 20, 1962: The Good Friday Experiment at Marsh Chapel.¹⁰
7. October 24, 1968: The U.S. bans possession of psilocybin and psilocin.²
8. October 27, 1970: The Controlled Substances Act places both in Schedule I.²
9. 1971: The UN Convention on Psychotropic Substances lists psilocybin and psilocin.¹¹
10. 1981: University of Oslo researchers document liberty cap use in Norway.²³
11. 2000: Johns Hopkins wins approval to restart psychedelic research.¹³
12. 2006: Griffiths and colleagues publish their landmark psilocybin study.¹⁴
13. 2018: FDA Breakthrough Therapy designation for COMPASS Pathways' psilocybin therapy.¹⁵
14. May 7, 2019: Denver becomes the first U.S. city to decriminalize psilocybin mushrooms.¹⁷
15. November 2020: Oregon passes Measure 109.¹⁹
16. November 2022: Colorado passes Proposition 122.¹⁹
17. April 2025: New Mexico enacts the Medical Psilocybin Act.²⁸
18. June 23, 2025: Compass reports the first Phase 3 psilocybin result.²⁰
19. April 18, 2026: Executive Order 14401 on psychedelic drug review.²²