Psychedelic Treatments for Psychiatric Disorders: A Systematic Review and Thematic Synthesis of Patient Experiences in Qualitative Studies

This review (2020) identified 15 studies (n=178) that used a variety of psychedelics to have overlapping therapeutic processes, were compared favorably over conventional treatments, and often elicited other positive changes beyond the specific diagnosis.

Abstract of Psychedelic Treatments for Psychiatric Disorders

“Introduction: Interest in the use of psychedelic substances for the treatment of mental disorders is increasing. Processes that may affect therapeutic change are not yet fully understood. Qualitative research methods are increasingly used to examine patient accounts; however, currently, no systematic review exists that synthesizes these findings in relation to the use of psychedelics for the treatment of mental disorders.

Objective: To provide an overview of salient themes in patient experiences of psychedelic treatments for mental disorders, presenting both common and diverging elements in patients’ accounts, and elucidating how these affect the treatment process.

Methods We systematically searched the PubMed, MEDLINE, PsycINFO, and Embase databases for English-language qualitative literature without time limitations. Inclusion criteria were qualitative research design; peer-reviewed studies; based on verbalized patient utterances; and a level of abstraction or analysis of the results. Thematic synthesis was used to analyze and synthesize results across studies. A critical appraisal of study quality and methodological rigor was conducted using the Critical Appraisal Skills Programme (CASP).

Results: Fifteen research articles, comprising 178 patient experiences, were included. Studies exhibited a broad heterogeneity in terms of substance, mental disorder, treatment context, and qualitative methodology. Substances included psilocybin, lysergic acid diethylamide (LSD), ibogaine, ayahuasca, ketamine and 3,4-methylenedioxymethamphetamine (MDMA). Disorders included anxiety, depression, eating disorders, post-traumatic stress disorder, and substance use disorders. While the included compounds were heterogeneous in pharmacology and treatment contexts, patients reported largely comparable experiences across disorders, which included phenomenological analogous effects, perspectives on the intervention, therapeutic processes and treatment outcomes. Comparable therapeutic processes included insights, altered self-perception, increased connectedness, transcendental experiences, and an expanded emotional spectrum, which patients reported contributed to clinically and personally relevant responses.

Conclusions: This review demonstrates how qualitative research of psychedelic treatments can contribute to distinguishing specific features of specific substances, and carry otherwise undiscovered implications for the treatment of specific psychiatric disorders.”

Authors: Joost J. Breeksema, Alistair R. Niemeijer, Erwin Krediet, Eric Vermetten & Robert A. Schoevers

Notes on Psychedelic Treatments for Psychiatric Disorders

This paper is included in our ‘Top 10 Articles on Psychedelics in the Treatment of Depression‘

• The 15 studies selected described the experiences of patients that took psychedelics for the purpose of treating a mental health disorder
• Patients reported high rates or report with the caregivers and compared the treatments favorably to conventional (previously tried) treatments
• Common (between the different drugs and settings) where the following themes: insight, altered self-perception, feelings of connectedness, transcendental experiences, expanded emotional spectrum, and (long-lasting) positive changes in quality of life
• This paper is the first to bring this qualitative analysis to psychedelics for mental disorders

“Our review revealed several connected therapeutic processes—seen across substances and for different disorders—that contributed to clinically signifcant and personally meaningful outcomes. Exploring patient experiences can increase our understanding of underlying therapeutic mechanisms and processes, the role of (extra) pharmacological factors in these treatment modalities, which may contribute to optimizing treatment context, and lead to improved clinical responses and personal benefts. Despite the heterogeneity of substance, setting, and population, these studies also suggest that, in addition to a shared phenomenology, psychedelic treatments exhibit similar therapeutic processes and result in comparable outcomes.”

Summary of Psychedelic Treatments for Psychiatric Disorders