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Top Questions

Who was Albert Hofmann?

What led to Albert Hofmann’s discovery of LSD?

What were Albert Hofmann’s views on the use of LSD?

Which psychotropic substances besides LSD did Albert Hofmann work with?

What is the Albert Hofmann Foundation?

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LSD speeds up brain waves and increases neural complexity, study finds • Oct. 22, 2026, 1:03 AM ET (News-Medical)

Albert Hofmann (born January 11, 1906, Baden, Switzerland—died April 29, 2008, Burg, Switzerland) was a Swiss chemist who discovered the psychedelic drug LSD (lysergic acid diethylamide), which he first synthesized in 1938 by isolating compounds found in ergot (Claviceps purpurea), a fungus affecting cereal grasses, especially rye.

Quick Facts
  • Born: January 11, 1906, Baden, Switzerland
  • Died: April 29, 2008, Burg, Switzerland
  • Known for: Discovering the psychedelic drug lysergic acid diethylamide (LSD)
  • Author of: LSD, mein Sorgenkind (1979), Insight, Outlook (1989), Hofmann’s Elixir: LSD and the New Eleusis (2008), and others

Early years

Despite his family’s lack of means, Hofmann spent an idyllic childhood exploring the hills surrounding Baden, though, as a teenager, he was forced to seek work when his father became ill. He graduated from the University of Zürich in 1929 with a doctorate in medicinal chemistry. Afterward he was hired by Sandoz Laboratories in Basel, where he was assigned to a program developing methods for synthesizing compounds found in medicinal plants. It was there, while testing the analeptic (stimulant) properties of ergot derivatives, that Hofmann stumbled upon LSD-25 (the 25th such derivative tested) in 1938.

Work with LSD

A “Trip” to Remember

Following his initial, accidental exposure to LSD, on April 16, 1943, Albert Hofmann intentionally ingested 0.25 mg (0.00000881849 ounce) of the substance at 4:20 ᴘᴍ on April 19, 1943, to investigate its effects. By 5:00 ᴘᴍ, he had begun feeling restless, anxious, and unable to speak clearly. Escorted by his laboratory assistant, Hofmann set off for his home on his bicycle—cars were restricted because World War II was in progress—and his experience escalated into what became the world’s first “acid trip.”

LSD’s discovery and Hofmann’s “trip”—both vehicular and neurological—are commemorated each year on April 19 as Bicycle Day, a celebration introduced in 1985 by psychology professor Thomas Roberts of Northern Illinois University.

Hofmann’s initial discovery was set aside for five years, until April 1943, when he returned to his earlier therapeutic research on the compound. After accidentally absorbing a small amount of the synthesized drug, he experienced dreamlike hallucinations. Following his initial experience, Hofmann purposely ingested the drug numerous times and concluded that it could be of significant use in psychiatric treatment. He spent years investigating LSD’s hallucinogenic properties in the belief that the drug would one day be useful in the therapeutic treatment of people with schizophrenia and other psychiatric conditions. Although he disapproved of the casual recreational use that came to define the drug in the 1960s, Hofmann maintained that LSD, when taken under controlled circumstances and with full knowledge of the possible effects, could prove useful in both psychiatric and spiritual contexts—an argument that he conveyed in his 1979 book LSD, mein Sorgenkind (LSD: My Problem Child, 1980).

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Investigations into other psychotropes

Hofmann also isolated methergine, a drug used to treat postpartum hemorrhaging, from ergot. However, most of his later research focused on the psychotropic qualities of various plants and fungi. In 1958 he synthesized psilocybin and psilocin, the hallucinogenic compounds in the mushroom Psilocybe mexicana, having been sent samples by an amateur mycologist intrigued by his work with LSD. In 1960 he discovered a compound similar to LSD in a species of morning glory (Rivea corymbosa), and in 1962 he traveled to Mexico to research the plant Salvia divinorum, though he was ultimately unable to discern its actively hallucinogenic components. While in Mexico, he was able to persuade a curandera (female shaman) to preside over a ritual that employed the compounds he had isolated from the Psilocybe mushroom, which grew naturally in the area. Hofmann also investigated the pharmacological properties of a number of other plants, including peyote, from which mescaline is derived.

Did You Know?

Later years and legacy

Hofmann, who had become director of natural products at Sandoz Laboratories in 1956, retired in 1971. In 1988 the Albert Hofmann Foundation, an organization advocating the responsible use of hallucinogens, was established in his honor. He contributed to several books, including The Road to Eleusis: Unveiling the Secret of the Mysteries (1978), which speculates that the Eleusinian Mysteries, a series of ancient Greek religious rites, were catalyzed by consumption of hallucinogenic mushrooms; The Botany and Chemistry of Hallucinogens (1973); and Plants of the Gods: Origins of Hallucinogenic Use (1979). Hofmann independently wrote Insight, Outlook (1989), concerning the perception of reality, and the posthumously published Hofmann’s Elixir: LSD and the New Eleusis (2008).