A convenient story that doesn’t hold up to the dates
A clean and satisfying story circulates in the psychedelic imagination: in the early 1960s, US lawmakers, frightened by the counterculture that had turned LSD into a sacrament, banned it and, in the process, wiped out the promising therapeutic research being conducted with it. It is a story with clear villains and a simple moral. The problem is that the dates do not quite add up, and it confuses two distinct phenomena: the criminalization of street use and the decline of clinical research.
When the events are organized chronologically, something else emerges. A good portion of researchers had already lost interest in the substance before the hippie phenomenon reached its peak and before Timothy Leary became the media face of the matter. The disillusionment did not come from the street, but from laboratories and regulatory offices.
Leary, Harvard, and the noise that drowned out what mattered
The well-known part of the story is the loudest. Leary and Richard Alpert were dismissed from Harvard in 1962, in an episode loaded with academic rivalries within a psychology department with a notable lineage—from William James to B. F. Skinner. From there, Leary, Alpert, and later Ralph Metzner continued their experiments outside of academia, drifting toward an almost messianic tone that, added to the antics of Ken Kesey, helped mass-popularize LSD among the youth.
It is worth clarifying a detail that is often caricatured: despite the dark legend, the Harvard psychedelic program had serious pretensions. And while happenings occupied the headlines, a portion of the cultural elite and the entertainment world consumed LSD discreetly in their homes. But all of this, however well-documented it may be, is the media wrapping of the matter, not its explanation. The underlying question—why clinical research faded—has a different answer.
The prohibition never reached the laboratory
The decisive, and most forgotten, fact is this: the prohibitions of the 1960s and 1970s targeted possession and recreational use, not research. California penalized LSD possession in 1966 and the rest of the United States in 1969, but none of those measures touched clinical and experimental uses. Even the 1971 Convention, with which the International Narcotics Control Board (INCB) placed LSD and other psychedelics on its most restrictive lists, still left room for science. As is the case with morphine or amphetamines, a substance can coexist in the illicit market and the medical field simultaneously.
That the subsequent anti-drug climate made life enormously difficult for anyone who wanted to research is true, but that came later. LSD research was not executed by decree: it gradually ran out of oxygen for other reasons.
Sandoz turns off the tap
LSD reached the American scientific community in 1949, courtesy of Sandoz, the Swiss company where Albert Hofmann had discovered its psychoactive effects in 1943. The anticipation was enormous: it was tested as a tool to explore mystical experience, to treat various mental disorders, and to address alcohol dependence, among other uses. For years, studies and therapies multiplied across the country.
The controversy surrounding the substance did have a real impact on research, but through a specific and unglamorous route: Sandoz stopped supplying LSD to US researchers. Here, a structural bottleneck of modern medicine appears. Bringing a drug to clinical use requires the backing of a pharmaceutical company that assumes the costly regulatory development; independent research can rarely afford it. Without Sandoz and without any US company willing to inherit that risk, processing the permits with the FDA to develop the drug became, in practice, unfeasible.
While hippies took LSD at their happenings, a portion of the cultural elite did the same in their homes. But neither of those two worlds explains why clinical research faded.
The wrong mold: the 1962 clinical trial
The other factor, perhaps the most profound, was methodological. In 1962, the Drug Amendments consolidated in the United States what is now the unquestionable standard: to market a drug, one must demonstrate its efficacy through controlled clinical trials, with randomization and double-blinding, so that neither the patient nor the researcher knows who receives the active ingredient and who receives the placebo. The goal—to control for expectation biases—is reasonable and has saved medicine from countless deceptions.
The underlying model, however, is of bacteriological root: a disease has a specific physical cause and an effective drug is one that neutralizes it, just as an antibiotic eliminates the bacteria responsible. It is a splendid scheme for infectious disease and quite clumsy for psychiatry. It is no coincidence that many key psychotropic drugs—antipsychotics, lithium—were discovered by chance, observing unexpected effects in patients treated for something else.
LSD fit especially poorly into that mold. It works on the patient’s mental contents; and although it acts on identifiable brain regions, those are not necessarily the regions that sustain the disorder. Separating the pharmacological effect from the therapeutic effect cleanly—exactly what a controlled trial requires—is almost impossible when context, expectation, and accompaniment are part of the treatment. After two decades of work, there was no consensus on its efficacy, and the new standard left psychedelics in a losing position from the start.
Protests, weariness, and an administrative sentence
There was resistance. Psychiatrists with years of experience—Humphry Osmond, Abram Hoffer, Al Hubbard—rejected the bacteriological corset as inoperative and argued before the FDA that the randomized clinical trial was not the only valid way to prove the efficacy of a drug, even less so in psychiatry. It did not prosper. The model was imposed on a global scale and many researchers simply lost their enthusiasm and turned to other things. All of this, it is worth insisting, before Leary’s figure monopolized everything.
Not everyone gave up: Stanislav Grof’s group at the Spring Grove State Hospital and others tried to adapt their studies to the new regulations. Meeting those requirements was so arduous that, in 1974, the US National Institute of Mental Health concluded that LSD lacked therapeutic applications; a sentence that, according to the critical reviewers themselves, was not handed down with all the desired equanimity.
Half a century later
The irony is that more than fifty years later, with finer statistical and biomedical methods, the research community has learned to design trials with LSD and psilocybin that do meet the standards of that model. Contemporary studies of psychedelic psychotherapy with terminal patients are the most visible example that the obstacle was never the substance, but the mold into which it was forced.
The moral is uncomfortable for the romantic narrative: therapeutic research with psychedelics was not executed by the culture war of the sixties. It was suffocated by the withdrawal of its only supplier and by a regulatory change that, unintentionally, sidelined an entire way of practicing psychiatry.
Critical reading
This reconstruction comes primarily from the work of historian Matthew Oram—especially his article on LSD psychotherapy and the 1962 Drug Amendments, published in the Journal of the History of Medicine and Allied Sciences—and from Steven J. Novak’s review of pre-Leary psychedelic research, which appeared in Isis. It is worth keeping some cautions in mind:
- Multiple causes, not just one. Arguing “it was the methodology and not the hippies” runs the risk of inverting the myth instead of overcoming it. It is reasonable to read the decline as a confluence of factors—regulatory, commercial, scientific, and cultural—without a single culprit.
- Enthusiasm is not equivalent to evidence. That the clinical trial model was a bad fit for LSD does not imply that those pioneering studies demonstrated what their defenders believed. A good portion suffered from small samples, lack of control, and overflowing expectations.
- Beware of the revival. Current research is promising, but it is subject to publication bias, cultural expectations, and market enthusiasm. It is advisable to follow it with the same critical rigor demanded of history.
- Risk reduction. Nothing above describes safe use outside of a controlled clinical framework. LSD can precipitate psychological crises, interacts with other drugs, and carries legal and health risks that no historical account nullifies.
