Albert Hofmann was a Swiss chemist born on January 11, 1906, in Baden and who passed away on April 29, 2008, at the age of 102 in Burg im Leimental. His discovery of LSD-25 in 1943 is considered one of the most significant coincidences in the history of science — a moment that permanently changed neuroscience, psychiatry, and ultimately the entire modern research landscape for lysergamides.

Albert Hofmann grew up as the eldest of four children in modest circumstances. His father worked as a toolmaker in a factory. Early on, Hofmann showed a fascination with nature — in his autobiography, he describes a mystical nature experience as a child that left a lasting impression on him.

After completing secondary school, Hofmann studied chemistry at the University of Zurich, where he earned his doctorate in 1929 with a thesis on the chitin structure of crustaceans. That same year, he joined the pharmaceutical department of Sandoz AG in Basel — a company that would later merge with Ciba-Geigy to form Novartis.

Hofmann's research focus at Sandoz was ergot (Claviceps purpurea) — a sac fungus that infects cereals (particularly rye) and produces a range of pharmacologically highly active alkaloids. Ergot had been known since the Middle Ages as both poison and medicine: it caused the dreaded "St. Anthony's Fire" (ergotism) but was also used to induce labor.

At Sandoz, Arthur Stoll had already begun isolating ergot alkaloids in the 1910s. Hofmann took over this work and developed it systematically. His goal: to use lysergic acid — the common chemical core of all ergot alkaloids — as a starting material for the synthesis of new compounds with medical potential.

Between 1935 and 1938, Hofmann synthesized a series of lysergic acid derivatives. He hoped to find a circulatory stimulant — a substance that could stimulate blood pressure and respiration. It was this search that led him to compound number 25.

On November 16, 1938, Hofmann synthesized lysergic acid diethylamide — the 25th compound in his series of systematic variations. He combined lysergic acid with diethylamine, a simple organic compound. The result bore the laboratory number LSD-25.

The substance was passed on to Sandoz's pharmacological department, where it was tested on laboratory animals. The results were — at first glance — disappointing. The animals showed a certain motor restlessness, but none of the hoped-for circulatory stimulant properties. An internal Sandoz report stated laconically: "The experiments were discontinued due to the lack of interesting properties."

LSD-25 disappeared into a drawer. For five years.

Why Hofmann returned to LSD-25 five years later is one of the great questions of science history. He himself wrote in his autobiography "LSD: My Problem Child":

"I had a peculiar presentiment that this substance might possess properties other than those established in the first investigation."

On April 16, 1943, Hofmann set up a new synthesis of LSD-25. While working in the laboratory, he suddenly began to feel unwell — dizzy, restless, slightly intoxicated. He interrupted his work and rode his bicycle home (cars were rationed during the war). At home, he experienced an approximately two-hour state of altered perception with vivid color phenomena.

Hofmann's conclusion: he must have absorbed a tiny amount of the substance through his skin during the synthesis. The effect from a dermal absorption of a trace amount was remarkable — and pointed to extreme potency.

The Crucial Question: How Much Had He Absorbed?

Hofmann later estimated that he could have absorbed at most 20–50 micrograms through his skin. For comparison: a typical pharmacologically active dose of a medication is in the milligram range — a thousand times higher. The potency of LSD-25 was without precedent in the history of pharmacology. To this day, LSD is considered one of the most potent known psychoactive substances: the effective dose lies in the range of 25–150 micrograms.

Three days after the accidental exposure, Hofmann decided on a deliberate self-experiment — a common, though today considered risky, practice in the scientific tradition of his time. He chose a dose of 250 micrograms (0.25 mg), which he believed to be conservative. In reality, it was an extraordinarily high dose.

At 4:20 PM, Hofmann took the substance orally. His laboratory journal meticulously records the following events:

• 4:50 PM — "Beginning dizziness, feeling of anxiety, visual disturbances, paralysis, desire to laugh"
• 5:00 PM — The notes break off. Hofmann asked his laboratory assistant to accompany him home.

What followed was the now-famous bicycle ride through Basel — "Bicycle Day." Hofmann later described kaleidoscopic color patterns, distorted proportions, and a deep sense of disorientation, followed by phases of calm and clarity. His neighbor, who brought him milk, appeared to him as a "malicious witch with a colored face."

The next morning, Hofmann felt refreshed and clear. In his report to his supervisor, he describes the experience matter-of-factly and recommends further systematic investigation.

In the following months and years, Hofmann and his colleagues at Sandoz conducted systematic studies. They determined dosages, investigated mechanisms of action, and tested the substance on willing subjects — all according to the (then-current) standards of scientific research.

In 1947, Werner Stoll — Arthur Stoll's son and a psychiatrist — published the first scientific study on the psychological effects of LSD in 16 test subjects (Schweizer Archiv für Neurologie und Psychiatrie). The results fascinated the psychiatric community.

Sandoz began supplying LSD-25 under the trade name "Delysid" to research institutes and psychiatrists — with the suggestion to use it as a tool in psychotherapy. The Delysid package insert is now a collector's item: it recommended that the therapist take the substance themselves to better understand their patients' experiences.

Between 1950 and 1965, over 1,000 scientific papers on LSD were published worldwide. The substance was used in the treatment of alcohol dependence, anxiety disorders, and neuroses — with promising, though methodologically not always flawless by today's standards, results.

Sandoz distributed LSD-25 from 1947 under the brand name Delysid as a psychiatric tool. The package insert contained a remarkable recommendation: therapists should explore the substance themselves to understand their patients' experiences. Between 1950 and 1965, over 1,000 scientific papers on LSD were published worldwide — an impressive number for a single substance.

The CIA simultaneously began its now-notorious MKUltra program (1953–1973), in which LSD was administered to subjects without their consent. At the same time, figures like Timothy Leary popularized the substance as a tool for consciousness expansion — far from Hofmann's vision of controlled research.

The backlash came swiftly: LSD was banned in the USA in 1966; in 1971, the UN Convention on Psychotropic Substances classified it as Schedule I — the most restrictive category. Sandoz ceased production. Clinical research ground to a halt for decades.

Hofmann watched this development with growing unease. In a letter to psychiatrist Stanislav Grof in 1971, he wrote: "What was born as a tool of science has become a plaything of politics."

According to an analysis by the University of Zurich (2019), the ban delayed psychiatric research by at least 30 years. Only from 2006 did institutions such as Johns Hopkins and Imperial College London begin to resume controlled research.

In 1979, Hofmann published his book "LSD: My Problem Child", which became the standard work on the subject. The title reveals Hofmann's ambivalent relationship with his discovery: he regarded LSD as a tool of immense potential whose uncontrolled spread outside scientific contexts he deeply regretted.

In an interview with the Frankfurter Allgemeine Zeitung (2006), the then-100-year-old said:

"LSD is a substance that must be treated with the greatest respect. It opened the gates to another world for me. But I always returned — that is the crucial point."

Hofmann's Later Work and Advocacy

Even after his retirement from Sandoz in 1971, Hofmann remained active:

• He continued researching natural products, particularly the active compounds of Mexican mushrooms (psilocybin) and morning glory (LSA/ergine)
• He published over 100 scientific papers throughout his career
• He publicly advocated for the resumption of controlled LSD research
• He was included in the British Daily Telegraph's list of "100 Greatest Living Geniuses" in 2007

Without Albert Hofmann's curiosity — his return to a substance dismissed as uninteresting — nothing we research today would exist. No 1P-LSD, no 1V-LSD, no 1Fe-LSD. The entire field of derivative research builds upon the molecule that a chemist in Basel first created on a November day in 1938.

But Hofmann's legacy goes beyond the molecule. He established principles that hold true to this day:

1. Systematic synthesis: Hofmann's methodical working through of lysergic acid variations is the model for today's derivative development
2. Careful documentation: His meticulous laboratory journal set standards for reporting
3. Respect for the substance: His lifelong plea for responsible use shaped research ethics
4. Interdisciplinary thinking: Hofmann bridged chemistry, botany, philosophy, and psychiatry — an approach that has become standard in modern psychedelic research

[LINK: The Complete Timeline of Derivatives → /geschichte-lsd-derivate/] [LINK: LSD-25 vs. Derivatives: The Comparison → /lsd-derivate-vs-lsd-25/]

Every year on April 19, research communities worldwide celebrate Bicycle Day. Events take place in over 42 countries — from academic symposia at universities to art exhibitions. The Multidisciplinary Association for Psychedelic Studies (MAPS) estimates that around 250,000 people participate in Bicycle Day events annually.

For us researchers, Bicycle Day is more than a memorial day. It is a reminder that great discoveries often lurk where no one is looking — in a forgotten laboratory number, a drawer full of abandoned projects, a "peculiar presentiment."

Albert Hofmann would probably have regarded today's diversity of lysergamide derivatives with his characteristic mix of fascination and caution. At one of his last public appearances, at the World Psychedelic Forum in Basel 2008, he said:

"The future of LSD research lies in the hands of a new generation. I only ask one thing of you: approach it with respect and curiosity. You need both."

We take that seriously.

[LINK: What Are LSD Derivatives? The Foundational Article → /was-sind-lsd-derivate/]

How old was Albert Hofmann?

Albert Hofmann lived to be 102 years old. He was born on January 11, 1906, in Baden (Switzerland) and passed away on April 29, 2008, in Burg im Leimental. He remained mentally active into his advanced years and attended scientific conferences — his last public appearance was at the World Psychedelic Forum in Basel 2008, just weeks before his death.

What is Bicycle Day?

Bicycle Day is observed annually on April 19 and commemorates Albert Hofmann's deliberate self-experiment with 250 micrograms of LSD-25 on April 19, 1943. The name refers to his now-famous bicycle ride from his laboratory at Sandoz to his home, during which the effects of the substance set in. According to estimates, over 250,000 people worldwide participate in Bicycle Day events each year.

Why did Hofmann call LSD his "problem child"?

The title of his 1979 book reflects Hofmann's ambivalent relationship with his discovery. He saw enormous therapeutic and scientific potential in the substance, but was deeply concerned about its uncontrolled use outside scientific contexts, which led to the worldwide ban and set research back by decades.