Sandoz’s Withdrawal of the LSD Supply

Sandoz’s Withdrawal of the LSD Supply was a pivotal break in the history of psychedelic research: in April 1966, the company pulled LSD-25 from circulation as controversy mounted, and many of the research programs that had depended on access to the drug soon closed. The decision did not resolve the conflict over what psychedelics were for. It sharply narrowed the space in which researchers could study them, pushing some work toward the underground and leaving later researchers to rebuild a clinical case for their use.

The Research Network Before the Withdrawal

In the 1950s, Sandoz LSD moved through a dispersed North American research network as well as through formal institutions. Al Hubbard traveled between centers, assisting Humphry Osmond and Abram Hoffer in Weyburn, meeting R. Gordon Wasson in Manhattan, and working with Betty Eisner, Sidney Cohen, and Oscar Janiger in Los Angeles. He carried ampules of Sandoz LSD along with practical knowledge of how to conduct sessions. At Hollywood Hospital in Vancouver, he helped establish an entire wing for treating alcohol dependence with LSD; he also founded two other treatment facilities in Canada. His work joined the supply of the drug to a developing therapeutic method and to a network of practitioners who shared techniques across distance.

That network extended beyond hospitals. After Hubbard guided Myron Stolaroff through a high-dose LSD session, Stolaroff began meeting with Ampex colleagues, including Don Allen and Willis Harman, to discuss the drug’s possible value for healthy people as well as patients. Hubbard visited Menlo Park to guide sessions and train others. In 1961, Stolaroff left Ampex and, with Harman, established the International Foundation for Advanced Study. The foundation obtained a drug research permit from the Food and Drug Administration and began work with LSD and mescaline supplied by Hubbard. These examples show why access to a dependable supply mattered: the drug supported clinical treatment, experimental research, training, and inquiries into creativity and human potential.

A Therapeutic Model Under Pressure

The supply crisis arrived amid a deeper dispute about how psychedelics should be understood and used. The psychotomimetic model treated their effects as resembling mental illness; the psycholytic model positioned them as an adjunct to psychoanalysis. Psychedelic therapy made a more disruptive claim. It centered on a single high-dose session intended to produce a conversion-like experience, and it challenged familiar distinctions between therapist and patient, sickness and health, and scientific treatment and spiritual practice. Its emphasis on set and setting also brought the work close to forms of healing associated with shamanism, unsettling a psychiatric establishment increasingly committed to biochemical explanations of the mind.

These differences made the first-wave research vulnerable beyond the question of supply. Psychedelic therapy proposed a different structure for treatment, not simply a new drug within existing routines. At the same time, researchers and guides were searching for a social and procedural container for powerful experiences. The withdrawal did not settle those debates, but it removed a crucial material support from the laboratories and treatment settings where they were being tested.

The 1966 Break and Its Consequences

In April 1966, seeking to distance itself from the controversy surrounding what Albert Hofmann called his problem child, Sandoz withdrew LSD-25 from circulation and turned over most of its remaining stocks to the U.S. government. At the time, roughly seventy research programs were under way. Many shut down after the withdrawal. By the end of the year, the book describes the broader project of psychedelic science as having collapsed.

The withdrawal was followed by public and regulatory conflict. In May, Timothy Leary and Sidney Cohen testified at Senate hearings on LSD, defending research and trying to distinguish legitimate use from the black market. Senator Robert F. Kennedy questioned why projects considered worthwhile only months earlier should now be abandoned and warned of the loss to medicine if the drugs were prohibited because of illicit use. The hearing made visible the divide between controlled research and unauthorized use, but it did not reverse the loss of the supply or restore the programs already threatened by the changing climate.

From Formal Research to Underground Practice

The end of legal research did not end all therapeutic use. When psychedelics were placed in Schedule I in 1970, Leo Zeff made the decision to continue his work underground. He developed practices for guiding sessions and trained other guides, contributing to a lineage that later researchers and practitioners would trace back to the first wave. Myron Stolaroff argued that anecdotal evidence from underground therapists such as Zeff helped shape the research that resumed in the late 1990s, alongside the studies conducted in the 1950s and 1960s. The boundary between the underground and university research was not absolute: some underground practitioners later helped train guides for clinical trials, and the Johns Hopkins team consulted guides about music in psilocybin sessions.

The renewed research gained wider recognition in December 2016, when results from the Johns Hopkins and NYU cancer studies were published together. Around 80 percent of patients in the two trials showed clinically significant reductions in anxiety and depression, with effects lasting at least six months. The studies were small and required replication, but their reception signaled a shift toward renewed medical legitimacy. That revival did not erase the institutional rupture of 1966. Instead, it made the withdrawal’s long aftermath visible: research that had once circulated through clinics and foundations survived partly through underground practice before returning, cautiously, to universities and hospitals.