Psychedelic Medicine
May 16, 2025
Roland R. Griffiths, William A. Richards, Robert L. Jesse et al.
14 citations
Background: Although historical writings, anthropological accounts, and experimental studies document associations between psilocybin use and religion, no prospective experimental study has investigated how the effects of psilocybin are experienced and interpreted by religious clergy. This exploratory study evaluated the overall safety and the acute and enduring effects of psilocybin in clergy....
Journal of Psychoactive Drugs
2024
Kelan Thomas, Robert L. Jesse, Nicky J. Mehtani et al.
4 citations
In recent years, policymakers have proposed and implemented regulatory changes promoting the deprioritization, decriminalization, or state-level legalization of one or more psychedelic substances, usually referencing data from clinical trials as reasons to support liberalizing drug control policies. As psychedelic policies continue to be drafted, personal possession limits may be considered for...
PLoS One
April 23, 2019
Roland R. Griffiths, Ethan Hurwitz, Alan K. Davis et al.
249 citations
Naturally occurring and psychedelic drug-occasioned experiences interpreted as personal encounters with God are well described but have not been systematically compared. In this study, five groups of individuals participated in an online survey with detailed questions characterizing the subjective phenomena, interpretation, and persisting changes attributed to their single most memorable God...
Journal of Psychopharmacology
October 11, 2017
Roland R. Griffiths, Matthew W. Johnson, William A. Richards et al.
528 citations
Psilocybin can occasion mystical-type experiences with participant-attributed increases in well-being. However, little research has examined enduring changes in traits. This study administered psilocybin to participants who undertook a program of meditation/spiritual practices. Healthy participants were randomized to three groups (25 each): (1) very low-dose (1 mg/70 kg on sessions 1 and 2)...
Journal of Psychopharmacology
August 31, 2016
Theresa M. Carbonaro, Matthew P. Bradstreet, Frederick S. Barrett et al.
541 citations
Acute and enduring adverse effects of psilocybin have been reported anecdotally, but have not been well characterized. For this study, 1993 individuals (mean age 30 yrs; 78% male) completed an online survey about their single most psychologically difficult or challenging experience (worst “bad trip”) after consuming psilocybin mushrooms. Thirty-nine percent rated it among the top five most...
Psychopharmacology
December 1, 2011
Roland R. Griffiths, Matthew W Johnson, William A Richards et al.
938 citations
This dose-effect study extends previous observations showing that psilocybin can occasion mystical-type experiences having persisting positive effects on attitudes, mood, and behavior. This double-blind study evaluated psilocybin (0, 5, 10, 20, 30 mg/70 kg, p.o.) administered under supportive conditions. Participants were 18 adults (17 hallucinogen-naïve). Five 8-h sessions were conducted...
Journal of Psychopharmacology
May 30, 2008
Roland R. Griffiths, Wa Richards, Mw Johnson et al.
883 citations
Psilocybin has been used for centuries for religious purposes; however, little is known scientifically about its long-term effects. We previously reported the effects of a double-blind study evaluating the psychological effects of a high psilocybin dose. This report presents the 14-month follow-up and examines the relationship of the follow-up results to data obtained at screening and on drug...
Psychopharmacology
July 7, 2006
Roland R. Griffiths, William A. Richards, U. Mccann et al.
1,684 citations
RationaleAlthough psilocybin has been used for centuries for religious purposes, little is known scientifically about its acute and persisting effects.ObjectivesThis double-blind study evaluated the acute and longer-term psychological effects of a high dose of psilocybin relative to a comparison compound administered under comfortable, supportive conditions.Materials and methodsThe participants...
Journal of Humanistic Psychology
April 1, 2004
Huston Smith, Charles S. Grob, Robert L. Jesse et al.
29 citations
Four decades ago, Huston Smith published one of the mostinfluential articles ever written on psychedelics, titled “Do Drugs HaveReligious Import?” As part of “The Oral History of PsychedelicResearch Project,” he was interviewed and invited to revisit thistopic. The interview covers his personal experiences, as well as the influences of psychedelic experiences on religious traditions...