Self-blinding citizen science to explore psychedelic microdosing
Using a self‑blinding citizen‑science protocol in the largest placebo‑controlled microdosing study to date (n=191), the authors found psychological outcomes improved after four weeks but with no significant differences between microdose and placebo groups. Small acute and anxiety effects appeared due to participants breaking blind, suggesting reported benefits of microdosing are largely placebo‑driven and demonstrating the feasibility of a low‑cost self‑blinding approach.
Authors
- Fernando Rosas
- Robin Carhart-Harris
- David Nutt
Published
Abstract
Microdosing is the practice of regularly using low doses of psychedelic drugs. Anecdotal reports suggest that microdosing enhances well-being and cognition; however, such accounts are potentially biased by the placebo effect. This study used a ‘self-blinding’ citizen science initiative, where participants were given online instructions on how to incorporate placebo control into their microdosing routine without clinical supervision. The study was completed by 191 participants, making it the largest placebo-controlled trial on psychedelics to-date. All psychological outcomes improved significantly from baseline to after the 4 weeks long dose period for the microdose group; however, the placebo group also improved and no significant between-groups differences were observed. Acute (emotional state, drug intensity, mood, energy, and creativity) and post-acute (anxiety) scales showed small, but significant microdose vs. placebo differences; however, these results can be explained by participants breaking blind. The findings suggest that anecdotal benefits of microdosing can be explained by the placebo effect.
Research Summary of 'Self-blinding citizen science to explore psychedelic microdosing'
Introduction
There is renewed scientific and clinical interest in psychedelic drugs such as LSD and psilocybin, principally in the context of psychedelics-assisted psychotherapy where a few large doses are given alongside psychotherapy. An alternative pattern of use, "microdosing", has become popular; it generally refers to repeated low doses (commonly 10-20% of a typical full dose) taken one to three times per week. Anecdotal reports and uncontrolled observational studies have suggested benefits for well-being, creativity and cognition, but these designs are vulnerable to expectancy, confirmation-bias and placebo effects, and randomised controlled laboratory studies to date have been small and focused on single acute doses rather than repeated use. The combination of (i) uncontrolled naturalistic evidence and (ii) underpowered controlled trials leaves uncertainty about whether reported benefits of microdosing are pharmacological or placebo-driven. Szigeti and colleagues set out to address these limitations by developing a low-cost, large-sample, placebo-controlled citizen-science approach they call "self-blinding". The study aimed to test whether repeated psychedelic microdosing produces superior accumulative, acute and post-acute effects compared with placebo on psychological state and cognitive function. The primary endpoint was after a core 4-week dosing period (week 5 of a 10-week protocol), and the investigators hypothesised that improvements from baseline would correlate with the number of microdoses taken and that acute/post-acute outcomes would be better on/after microdose days compared with placebo days. The design combined prospective online assessments and cognitive testing with randomisation and participant-implemented blinding to obtain a large, ecologically valid sample at minimal cost.
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Study Details
- Study Typeindividual
- Journal
- Compounds
- Topics
- Authors
- APA Citation
Szigeti, B., Kartner, L., Blemings, A., Rosas, F., Feilding, A., Nutt, D. J., Carhart-Harris, R. L., & Erritzoe, D. (2021). Self-blinding citizen science to explore psychedelic microdosing. eLife, 10. https://doi.org/10.7554/eLife.62878
References (2)
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