Skip to content

Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects.

Roland R. Griffiths, Matthew W Johnson, William A Richards, Brian D. Richards, Una D. Mccann, Robert L. Jesse

Psychopharmacology December 1, 2011 DOI: 10.1007/s00213-011-2358-5 (opens in new tab)

Read Full Text
Relevant Not relevant

Study at a glance

AI-extracted from the abstract
Characteristics Randomized controlled trial Double-blind Peer reviewed
Sample size 18
Population Healthy adults, mostly hallucinogen-naïve
Intervention Psilocybin
Dose 0, 5, 10, 20, 30 mg/70 kg, p.o.
Duration Five 8-hour sessions at 1-month intervals, with follow-up at 1 month and 14 months
Topics Psilocybin Psychedelic-assisted therapy Mystical experience
Keywords Psychedelics Entheogens Hallucinogens Personal growth Self-development Self-improvement Transformation Well-being Positive change Lasting change Mystical experiences Spiritual experiences Peak experiences Transcendence Profound awe Psilocybin therapy Clinical trials Therapeutic research Drug studies Mental health treatment
Citations 938
Key findings Under supportive conditions, 20 and 30 mg/70 kg psilocybin occasioned mystical-type experiences having persisting positive effects on attitudes, mood, and behavior.

Abstract

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 individually for each participant at 1-month intervals. Participants were randomized to receive the four active doses in either ascending or descending order (nine participants each). Placebo was scheduled quasi-randomly. During sessions, volunteers used eyeshades and were instructed to direct their attention inward. Volunteers completed questionnaires assessing effects immediately after and 1 month after each session, and at 14 months follow-up. Psilocybin produced acute perceptual and subjective effects including, at 20 and/or 30 mg/70 kg, extreme anxiety/fear (39% of volunteers) and/or mystical-type experience (72% of volunteers). One month after sessions at the two highest doses, volunteers rated the psilocybin experience as having substantial personal and spiritual significance, and attributed to the experience sustained positive changes in attitudes, mood, and behavior, with the ascending dose sequence showing greater positive effects. At 14 months, ratings were undiminished and were consistent with changes rated by community observers. Both the acute and persisting effects of psilocybin were generally a monotonically increasing function of dose, with the lowest dose showing significant effects. Under supportive conditions, 20 and 30 mg/70 kg psilocybin occasioned mystical-type experiences having persisting positive effects on attitudes, mood, and behavior. Implications for therapeutic trials are discussed.

In the evidence

This study is part of the evidence base for 4 syntheses in the library. Here is how each one recorded it.

  • State of the evidence: Psilocybin and psychedelic-assisted therapy Supports

    Doses of 20-30 mg/70 kg occasioned mystical-type experiences in 72% and were rated as producing sustained positive changes in attitudes, mood, and behavior at 14 months.

    Synthesized

  • State of the evidence: Mystical experience Supports

    At 20 and/or 30 mg/70 kg, 72% of volunteers had mystical-type experiences, which were rated as personally and spiritually significant with sustained positive changes in attitudes, mood, and behavior undiminished at 14 months.

    Synthesized

  • State of the evidence: Psilocybin Supports

    20 and 30 mg/70 kg psilocybin occasioned mystical-type experiences with persisting positive changes in attitudes, mood, and behavior at 14 months, though 39% experienced extreme anxiety/fear at high doses.

    Synthesized

  • State of the evidence: Psychedelic-assisted therapy Supports

    High doses of psilocybin occasioned mystical-type experiences and were rated as producing sustained positive changes in attitudes, mood, and behavior, undiminished at 14 months.

    Synthesized

Comparable studies

Other randomized controlled trials on psilocybin and psychedelic-assisted therapy, most cited first.

Study Year Design Participants
Percentage of Heavy Drinking Days Following Psilocybin-Assisted Psychotherapy vs Placebo in the Treatment of Adult Patients With Alcohol Use Disorder Adults aged 25–65 with DSM-IV alcohol dependence and at least 4 heavy drinking days in... 2022 Randomized controlled trial n = 95
Increased global integration in the brain after psilocybin therapy for depression. Patients with treatment-resistant depression and patients with major depressive disorder 2022 Open-label trial and double-blind phase II randomized controlled trial
Single-dose psilocybin-assisted therapy in major depressive disorder: A placebo-controlled, double-blind, randomised clinical trial. Adults diagnosed with major depressive disorder and no unstable somatic conditions 2023 Double-blind, randomised clinical trial n = 52
Implications for psychedelic-assisted psychotherapy: functional magnetic resonance imaging study with psilocybin Healthy participants 2012 Randomized controlled trial n = 10
The Watts Connectedness Scale: a new scale for measuring a sense of connectedness to self, others, and world Adults who had a planned psychedelic experience (online surveys) and adults with major... 2022 Scale validation with data from two prospective observational online surveys and a double-blind randomized controlled trial n = 1,278

Citations in the library

Cited by 743

and 738 more in the library

Cites 14

and 9 more in the library

Related reading

Explore topics

Psilocybin Psychedelic-assisted therapy Mystical experience Anxiety Mysticism

By condition and practice

Psilocybin and psychedelic-assisted therapy