For starters, assessing risk is tricky. A lot of what both scientists and the general public think they know about the potential risks of psychedelic use comes from the first wave of research and experimentation in the 1950s, 60s and 70s. But this body of knowledge includes studies that wouldn’t meet today’s scientific standards; urban legends; and sensational, unsubstantiated news stories.
Also, reporting and describing adverse events is often subjective to some extent, psychiatrist Rick Strassman noted in a 1984 paper. Some people consider the drug-induced state itself pathological, he wrote, while others believe even the worst reactions are part of “throwing off ‘straight’ society’s ‘shackles’ and in reaching a ‘higher’ level of consciousness.” And many of the more recent studies on the potential harms of LSD and other hallucinogens draw on data from the 1950s and 60s. Those studies had a lot of methodological problems; many lack baseline data about their subjects, didn’t use placebos and/or failed to specify the source of the drug or the setting in which it was given.