Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects.
Psychopharmacology December 1, 2011 Roland R Griffiths, Matthew W Johnson, William A Richards et al. 938 citations
Psilocybin can produce mystical-type experiences that lead to lasting positive changes in attitudes, mood, and behavior. In a double-blind study, 18 adults (17 with no prior hallucinogen use) received 0, 5, 10, 20, or 30 mg/70 kg psilocybin in five sessions under supportive conditions. At the two highest doses, 72% of volunteers reported a mystical-type experience, and 39% experienced extreme anxiety or fear. One month later, participants rated these sessions as having substantial personal and spiritual significance, with the ascending dose sequence showing greater positive effects. At 14 months, these positive ratings remained undiminished and were consistent with observer reports. The effects generally increased with dose.