AdolescentsMajor Depressive Disorder (MDD)Treatment-Resistant Depression (TRD)Depressive DisordersSubstance Use Disorders (SUD)SchizophreniaLSD

Psychedelics in the treatment of unipolar mood disorders: a systematic review

This meta-analysis (n=423) of studies before prohibition (1949-73) of treating unipolar mood disorders (depression) showed that, besides the many flaws of the studies, the results were positive (79% of participants showed improvements, few side-effects).

Authors

  • James Rucker
  • Allan Young
  • Luke Jelen

Published

Journal of Psychopharmacology
meta Study

Abstract

Unipolar mood disorders, including major depressive disorder and persistent depressive disorder (dysthymia), confer high rates of disability and mortality and a very high socioeconomic burden. Current treatment is suboptimal in most cases and there is little of note in the pharmaceutical development pipeline. The psychedelic drugs, including lysergic acid diethylamide and psilocybin, were used extensively in the treatment of mood disorders, and other psychiatric conditions, before their prohibition in the late 1960s. They are relatively safe when used in medically controlled environments, with no reported risk of dependence. Here, we present a systematic review of published clinical treatment studies using psychedelics in patients with broadly defined UMD, and consider their place in psychiatry. Whilst all of the included studies have methodological shortcomings, of 423 individuals in 19 studies, 335 (79.2%) showed clinician-judged improvement after treatment with psychedelics. A recently completed pilot study in the UK favours the use of psilocybin with psychological support in treatment resistant depressive disorder. The evidence overall strongly suggests that psychedelics should be re-examined in modern clinical trials for their use in unipolar mood disorders and other non-psychotic mental health conditions.

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Research Summary of 'Psychedelics in the treatment of unipolar mood disorders: a systematic review'

Introduction

Unipolar mood disorders (UMD), comprising major depressive disorder and persistent depressive disorder, are common, recurrent and costly conditions that cause substantial morbidity and mortality. Against a backdrop of limited new pharmacological development and suboptimal outcomes for a substantial minority of patients, historical reports from the mid-20th century indicate that classical psychedelics—most notably LSD and, less commonly, mescaline—were used therapeutically and sometimes produced marked, durable clinical improvements. Earlier research also raised safety concerns driven largely by recreational harms and sociopolitical factors, contributing to legal prohibition and a hiatus in clinical investigation. This paper systematically collates the pre-prohibition clinical literature on psychedelics for broadly defined unipolar mood disorders (including contemporaneous labels such as "neurotic" and "psychoneurotic" disorders) with the explicit aim of appraising whether these agents merit reinvestigation in modern, rigorously designed clinical trials. The review therefore synthesises study characteristics, outcomes and safety reports from published clinical treatment studies to inform debate about contemporary trial design and research priorities.

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