Psychedelics have been used for spiritual purposes, healing, and growth for thousands of years, even possibly as far back as prehistoric times.
Psychoactive substances such as psilocybin found in mushrooms and mescaline found in cacti, have played important roles in many cultures around the world.
Research on psychedelics seems to have started when mescaline was identified in the peyote cactus in the late nineteenth and early twentieth centuries. Albert Hoffman discovered LSD in Switzerland in 1943. This increased interest in psychedelics among other scientists. During the 1950s and 1960s, psychedelic research grew as scientists attempted to understand more about the psychedelic experience and how it could potentially be used for therapeutic use in for mental illness. Most research took place in the USA, the Czech Republic and Canada.
Psychedelics became more widely used in recreational settings in the USA and influenced mainstream culture, as evidenced in music and literature. However, there was a backlash against psychedelics due to politics, misinformation, and fear. In 1970, the USA placed psychedelics in Schedule I of the Controlled Substances Act, deeming them to have no medical value, and this prohibition spread internationally which rapidly halted psychedelic research.
Later that decade, MDMA, a non-classic psychedelic, was discovered, but was also classified as a Schedule I drug in 1985 in the USA and around the world a year later. Despite this psychedelics continued to be used for therapeutic, exploratory, and recreational purposes.
Research into psychedelics as treatment for mental health problems died off in the 1970s and remained slow for several decades. However, advocates such as the Multidisciplinary Association for Psychedelic Studies (MAPS) continued efforts to obtain legal permission to conduct psychedelic research and there has been a recent resurgence of well-controlled clinical trials providing strong preliminary evidence for the use of some psychedelics for therapeutic purposes.
