OPEN Foundation

Search
Close this search box.

A Meta-Analysis of Placebo-Controlled Trials of Psychedelic-Assisted Therapy

Share This Post

Abstract

After a two-decade hiatus in which research on psychedelics was essentially halted, placebo-controlled clinical trials of psychedelic-assisted therapy for mental health conditions have begun to be published. We identified nine randomized, placebo-controlled clinical trials of psychedelic-assisted therapy published since 1994. Studies examined psilocybin, LSD (lysergic acid diethylamide), ayahuasca (which contains a combination of N,N-dimethyltryptamine and harmala monoamine oxidase inhibitor alkaloids), and MDMA (3,4-methylenedioxymethamphetamine). We compared the standardized mean difference between the experimental and placebo control group at the primary endpoint. Results indicated a significant mean between-groups effect size of 1.21 (Hedges g), which is larger than the typical effect size found in trials of psychopharmacological or psychotherapy interventions. For the three studies that maintained a placebo control through a follow-up assessment, effects were generally maintained at follow-up. Overall, analyses support the efficacy of psychedelic-assisted therapy across four mental health conditions – post-traumatic stress disorder, anxiety/depression associated with a life-threatening illness, unipolar depression, and social anxiety among autistic adults. While study quality was high, we identify several areas for improvement regarding the conduct and reporting of trials. Larger trials with more diverse samples are needed to examine possible moderators and mediators of effects, and to establish whether effects are maintained over time.
Luoma, J. B., Chwyl, C., Bathje, G. J., Davis, A. K., & Lancelotta, R. (2020). A Meta-analysis of Placebo-controlled Trials of Psychedelic-assisted Therapy. Journal of Psychoactive Drugs, 1-11., https://doi.org/10.1080/02791072.2020.1769878
Link to full text

OPEN Foundation

Join ICPR 2022 Online!

ICPR features world-leading experts from many academic disciplines, including psychiatry, psychology, neuroscience, anthropology, ethnobotany, and philosophy who come together to give a scientific conference for academics, therapists, researchers, clinicians, policymakers, and members of the public. Get your ICPR 2022 livestream ticket today and use the code OPENLIVE30 at checkout for a €30 discount.

Learn More

INTERESTED IN PSYCHEDELIC RESEARCH AND THERAPIES?

Subscribe to our new OPEN-Minded newsletter to stay in the loop, hear about our events, and become a part of a community dedicated to advancing psychedelics.

By clicking subscribe, I confirm to receive emails from the OPEN Foundation and agree with its privacy policy.

16 July - NDE's and Psychedelic Experiences: Commonalities & Insights

X