Major Depressive Disorder (MDD)Depressive DisordersAnxiety DisordersObsessive-Compulsive Disorder (OCD)Alcohol Use Disorder (AUD)Substance Use Disorders (SUD)Palliative & End-of-Life DistressSchizophreniaHealthy VolunteersSafety & Risk ManagementMedicinal Chemistry & Drug DevelopmentPsilocybinAyahuascaLSD

Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies

This systematic review (2020) looked at 10 modern studies (n=188) on psychedelics (psilocybin, ayahuasca, LSD) for the treatment of a variety of mental health disorders. The review found the studies to provide evidence for efficacy (up to months later) and safety.

Authors

  • Robin Carhart-Harris
  • David Nutt
  • David Erritzoe

Published

Acta Psychiatrica Scandinavica
meta Study

Abstract

Objective

To conduct a systematic review of modern-era (post-millennium) clinical studies assessing the therapeutic effects of serotonergic psychedelics drugs for mental health conditions. Although the main focus was on efficacy and safety, study characteristics, duration of antidepressants effects across studies, and the role of the subjective drug experiences were also reviewed and presented.

Method

A systematic literature search (1st Jan 2000 to 1st May 2020) was conducted in Pubmed and Psychinfo for studies of patients undergoing treatment with a serotonergic psychedelic.

Results

Data from 16 papers, representing 10 independent psychedelic-assisted therapy trials (psilocybin=7, ayahuasca = 2, LSD=1) were extracted, presented in figures and tables, and narratively synthesized and discussed. Across these studies, a total of 188 patients suffering either anxiety and/or depressive symptoms associated with cancer (C-RPD), major depressive disorder (MDD), obsessive compulsive disorder (OCD) or substance use disorder (SUD) were included. The reviewed studies established feasibility and evidence of safety, alongside promising early data of efficacy in the treatment of depression, anxiety, OCD, and tobacco and alcohol use disorders. For a majority of patients, the therapeutic effects appeared to be long-lasting (weeks-months) after only 1 to 3 treatment session(s). All studies were conducted in line with guidelines for the safe conduct of psychedelic therapy and no severe adverse events were reported.

Conclusion

The resurrection of clinical psychedelic research provides early evidence for treatment efficacy and safety for a range of psychiatric conditions, and constitutes an exciting new treatment avenue in a health area with major unmet needs.

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Research Summary of 'Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies'

Introduction

Andersen and colleagues frame the review in the context of a long history of psychedelic research beginning in the 1950s, when LSD, psilocybin, DMT and mescaline were investigated both as tools for modelling psychosis and as potential therapeutics across a range of psychiatric conditions. Interest in these compounds waned after restrictive legislation in the 1970s and methodological shortcomings in many early studies, but more recent decades have seen renewed scientific work using modern imaging, epidemiology and controlled experimental designs. Naturalistic and experimental studies have suggested associations between past psychedelic use and reduced psychological distress, and laboratory studies in healthy volunteers report sustained improvements in well-being and personality measures well beyond the drugs' short pharmacokinetic presence. This paper sets out to collate modern-era (post-2000) clinical studies that administered classic serotonergic psychedelics (psilocybin, LSD, ayahuasca/DMT, mescaline) in controlled settings for psychiatric indications. The stated aim is to provide an overview of preliminary evidence for efficacy and safety, the duration of therapeutic effects, and the relationship between the subjective psychedelic experience and clinical outcomes. The authors follow PRISMA-guided systematic review methods to identify and synthesise relevant trials from 2000 to May 1 2020.

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Study Details

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