How Psychedelics Came to Be Placed Under the Strictest International Control

Written by Måns Bergkvist

Psychedelics have once again come into focus in research and medicine. Their therapeutic potential is being explored in clinical studies, barriers to research are increasingly being questioned, and even within the UN system, the tone today is more nuanced than it was a few decades ago. Yet substances such as LSD, psilocybin, and mescaline remain subject to the strictest level of international control under the 1971 Convention on Psychotropic Substances. But how did they end up there?

In our recently published study, “Fear and Loathing in the United Nations: The Establishment of International Control of Psychedelics Through the 1971 Convention on Psychotropic Substances,” we returned to archival material from the United Nations, the Swedish National Archives, and the U.S. National Archives to trace the diplomatic process through which psychedelics were brought under the 1971 Convention. What emerges is not a story of scientific knowledge being translated straightforwardly into international regulation. Rather, it is a process shaped by political and economic interests, alarmist media coverage, Cold War tensions, broader anxieties about youth culture and social change in the 1960s and shifting priorities at crucial moments.

Background on the 1971 Convention

To understand how psychedelics came to be placed under international control, one must first understand why the issue of international control of other substances was raised in the first place. The 1961 Single Convention primarily covered plant-based drugs such as opium, coca, and cannabis. But it left clear gaps when it came to synthetic substances, above all sedatives and stimulants such as barbiturates and amphetamines. These substances were already causing problems in several countries, but they also had established medical uses and were backed by powerful pharmaceutical interests in economically strong Western states. Sweden and Japan, which faced extensive problems with amphetamine misuse, therefore pushed for stricter international control, while several producer countries opposed such efforts. The road toward what later became the Psychotropic Convention thus did not begin with psychedelics, but with the question of how psychoactive substances outside the existing conventions should be regulated.

This process must be understood against the background of how such matters were handled within the UN system. The Commission on Narcotic Drugs (CND) was, and still is, the central diplomatic forum where new control issues were raised, debated, and advanced. At the same time, the World Health Organization was tasked with assessing the medical usefulness and harmful effects of substances. The road to the 1971 diplomatic conference in Vienna, where the convention was adopted, was marked by a long-running interplay among political priorities, expert assessments, and repeated negotiations among member states.

Pharmacological and Cultural Factors of International Control

Psychedelics unexpectedly entered this process. In the late 1950s and early 1960s, the CND had a standing agenda item on substances not yet under international control. LSD was first raised in 1963, when the French chair of the meeting said that he had read in the press that the substance was being abused. The following year, a WHO expert committee also discussed hallucinogenic substances, but the focus remained on other groups of psychoactive drugs. The turning point came in 1966, when an ad hoc committee appointed to deal with synthetic stimulants, sedatives, and tranquilizers suddenly singled out LSD as a particularly urgent international problem. This became a defining moment in the process. From having been a marginal issue, psychedelics thereafter became the highest-priority group among the substances not yet covered by international control.

The placement of psychedelics in Schedule I, the strictest level of control in the 1971 Convention, might be taken to suggest that science at the time showed them to be exceptionally dangerous. The archival material, however, points in another direction. The state of knowledge about psychedelic substances was very limited during the 1960s; there were genuine concerns about adverse reactions, especially in relation to LSD, but much remained unclear, and the support for the alarmist rhetoric that soon became dominant was weak. Available studies did not indicate a strong potential for dependence, and when serious cases of harm were discussed, it was often difficult to establish causality. Yet various UN bodies described LSD in highly sweeping terms as a serious or acute threat, usually without specifying the empirical basis for such claims. For substances such as psilocybin, DMT, and mescaline, the discussion was even thinner. When the CND considered the ad hoc committee’s report in 1966, the committee’s British rapporteur acknowledged that . The ad hoc committee “had assumed that all [psychedelics] should be treated as being dangerous until advice was received to the contrary.”

To understand the gap between evidence and regulation, one must look beyond pharmacology. During the 1960s, psychedelics became associated with youth culture, student movements, the counterculture, and a broader questioning of authority.

This can be exemplified with the opening statements at the 1971 conference, as the U.S. delegate expressed that the use of psychedelic substances influenced social and political protesters among university students; in turn, the “public was alarmed in consequence.”

In UN discussions, they were presented not only as a health risk but also as a social threat: linked to unrest, reduced productivity, protest, and the breakdown of established norms. The media played an important role in this. Coverage focused not only on alleged harms such as psychosis, suicide, and chromosomal damage, but also on the idea that LSD was spreading like an epidemic, especially among young people and in new social settings. Psychedelics thus came to appear not merely as a health risk, but as a growing social problem. Their path into the UN system, therefore, bears clear traces of what sociologists call moral panic: a situation in which public fears and political reactions become disproportionate to the available evidence and the actual scale of the problem.

Additional Factors

The logic of the Cold War also played a role. Within UN diplomacy, Eastern Bloc countries often described drug use as an expression of the moral and social decay of capitalist societies, while Western countries more often framed drug control as a matter of public health and social order. That both sides could nonetheless converge around demands for strict control had less to do with a shared view of the evidence than with the fact that regulation served different, but compatible, political purposes. Psychedelics thus also became an arena for broader ideological competition within the UN system. Indeed, a U.S. Department of Justice report in 1972 found that international drug negotiations were heavily driven by Cold War politics. The U.S. and the Soviet Union competed for influence, pressuring countries to align with their blocs, making voting decisions reflect geopolitical loyalties rather than actual drug policy concerns.

Another central factor was that psychedelic substances lacked strong defenders. Amphetamines and barbiturates had powerful economic interests behind them. They were commercially important, medically established, and supported by the pharmaceutical industry, which actively opposed strict international control. Psychedelics had no comparable protection. By the mid-1960s, pharmaceutical companies had largely lost interest in LSD, the patent had expired, and commercial prospects were uncertain. Plant-based psychedelics were also difficult to patent and commercialize. This made psychedelics politically vulnerable: symbolically charged, frightening in the media, and lacking a strong lobby. In that sense, psychedelics came to function as a “good enemy” within the international control system.

The 1971 Convention

By the time the issue reached the Vienna Convention in 1971, the outcome was not entirely predetermined. The United States, which otherwise often pushed for strict international drug control, played an important role in this part of the negotiations in preserving a limited space for scientific research and possible medical use. On the issue of psychedelic plants, moreover, the United States formed part of a broader group that included countries such as Mexico and Australia, which argued that wild-growing plants should be left outside the scope of regulation, among other things, to protect religious uses and avoid impractical rules. This contrasted calls from some nations to take the opportunity to allow the 1971 convention to “eradicate” such traditions.

The outcome was that substances such as psilocybin and mescaline were placed under strict control. In contrast, plants such as psilocybin mushrooms and peyote were excluded from the convention.

It is important to emphasize that the weak scientific basis for the regulation of psychedelics is not some historical anomaly. On the contrary, research on other substances within and around the international control system suggests that this has often been the rule rather than the exception. Historical studies of cannabis and the coca leaf have shown how moral panic, political pressure, colonial assumptions, weak evidence, and inadequate scientific scrutiny shaped their place in the international control system. The history of psychedelics fits into this broader pattern.

Ramifications

This history is not merely of academic interest. If the original classification of psychedelics was shaped by moral panic, political pressures, and incomplete knowledge, there are also reasons to scrutinize its continuing authority. Today, a growing body of research points to the therapeutic potential of psychedelics, and authorities and expert bodies have also noted that the current international classification may create obstacles to research and treatment. At the same time, the legacy of the 1971 Convention remains strong: it continues to shape global drug policy, national legislation, and the conditions for the production of scientific knowledge.

History does not in itself provide the answer to how regulation should look today. But it does show that the current order should not be treated as neutral, self-evident, or immutable. On the contrary, as psychedelics re-enter scientific and medical debate, there are good reasons to re-examine the foundations of their international regulation. The question is no longer only whether psychedelics can be safe and effective, but also whether the systems that govern them rest on a sufficiently solid foundation.

Read the Paper