Anxiety DisordersDepressive DisordersSet & Setting

Antidepressant effects of a psychedelic experience in a large prospective naturalistic sample

In a large prospective naturalistic sample of people with baseline depressive symptoms, self‑reported depressive scores on the QIDS‑SR‑16 fell significantly at two and four weeks after a planned psychedelic experience. Larger improvements were associated with a medicinal motive, prior psychedelic use, higher dose and experiencing an emotional breakthrough, supporting therapeutic potential and highlighting roles for both pharmacological and non‑pharmacological factors.

Authors

  • Robin Carhart-Harris
  • David Nutt
  • David Erritzoe

Published

Journal of Psychopharmacology
individual Study

Abstract

Background

Over the last two decades, a number of studies have highlighted the potential of psychedelic therapy. However, questions remain to what extend these results translate to naturalistic samples, and how contextual factors and the acute psychedelic experience relate to improvements in affective symptoms following psychedelic experiences outside labs/clinics. The present study sought to address this knowledge gap.

Aim

Here, we aimed to investigate changes in anxiety and depression scores before versus after psychedelic experiences in naturalistic contexts, and how various pharmacological, extrapharmacological and experience factors related to outcomes.

Method

Individuals who planned to undergo a psychedelic experience were enrolled in this online survey study. Depressive symptoms were assessed at baseline and 2 and 4 weeks post-psychedelic experience, with self-rated Quick Inventory of Depressive Symptomatology (QIDS-SR-16) as the primary outcome. To facilitate clinical translation, only participants with depressive symptoms at baseline were included. Sample sizes for the four time points were N = 302, N = 182, N = 155 and N = 109, respectively.

Results

Relative to baseline, reductions in depressive symptoms were observed at 2 and 4 weeks. A medicinal motive, previous psychedelic use, drug dose and the type of acute psychedelic experience (i.e. specifically, having an emotional breakthrough) were all significantly associated with changes in self-rated QIDS-SR-16.

Conclusion

These results lend support to therapeutic potential of psychedelics and highlight the influence of pharmacological and non-pharmacological factors in determining response. Mindful of a potential sample and attrition bias, further controlled and observational longitudinal studies are needed to test the replicability of these findings.

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Research Summary of 'Antidepressant effects of a psychedelic experience in a large prospective naturalistic sample'

Introduction

Depression treatment advances have been limited since the 1980s, and interest in psychedelic-assisted interventions has re-emerged since the mid-2000s. Earlier controlled trials and population studies have indicated possible antidepressant and anxiolytic effects after one or a few psychedelic doses, and prior work has emphasised the importance of contextual or "set and setting" variables and the quality of the acute psychedelic experience (for example mystical-type experiences, challenging experiences and emotional breakthrough) in mediating longer-term outcomes. This study aimed to extend that literature into a large prospective naturalistic sample by examining changes in depressive and anxiety symptoms before versus after a self-initiated psychedelic experience. Specifically, the investigators tested whether drug dose, motive for use (with a focus on a medicinal motive), prior psychedelic experience and acute experience quality (emotional breakthrough, mystical-type and challenging experiences) predicted symptom change. Depressive symptoms measured by the Quick Inventory of Depressive Symptomatology (QIDS-SR-16) served as the primary outcome, assessed at baseline and 2 and 4 weeks post-experience via an online prospective survey platform.

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Study Details

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