An open-label pilot study of psilocybin-assisted therapy for binge eating disorder.
Jesse Dallery, Jennifer L Miller, Jeff Boissoneault, Lauren Harvey, Lindsey Ives, Alexandra Knerr, Shelby Blaes, Morgan N. Ransom, Melissa S. Munson, James P. Gilligan, Michael H. Silverman, Peter R. Guzzo, Beverlee Loeser
Journal of Eating Disorders January 3, 2026 DOI: 10.1186/s40337-025-01508-3 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Open-label pilot study Peer reviewed |
|---|---|
| Sample size | 5 |
| Population | Adults with binge-eating disorder |
| Interventions | Psilocybin Acceptance and Commitment Therapy (ACT)-based psychotherapy |
| Dose | 25 mg |
| Duration | 14-week follow-up |
| Topics | Psilocybin |
| Keywords | Binge-eating disorder Neuroimaging |
| Citations | 1 |
| Key points | A single 25 mg dose of psilocybin combined with ACT was feasible, well-tolerated, and associated with sustained reductions in binge-eating frequency and improvements in mood and psychological flexibility. |
Abstract
Binge Eating Disorder (BED) is the most prevalent eating disorder and is associated with psychiatric comorbidities, health impairments, and decreased quality of life. Emerging evidence suggests that psilocybin-assisted therapy may promote cognitive and emotional flexibility and disrupt maladaptive behavioral patterns, making it a promising candidate for BED treatment. This open-label pilot study evaluated the feasibility, safety, and preliminary therapeutic effects of a single 25 mg dose of psilocybin administered in the context of Acceptance and Commitment Therapy (ACT)-based psychotherapy in adults with BED (N = 5). Primary outcomes included safety measures, and exploratory outcomes included self-reported binge eating frequency, depression, anxiety, psychological flexibility, anthropometric indices, and neuroimaging biomarkers assessed over a 14-week follow-up. Psilocybin was well tolerated, with no serious adverse events. Reductions in self-reported binge eating frequency were observed across all participants and sustained through week 14. Improvements were also noted in depression, anxiety, and psychological inflexibility. Three participants showed reductions in body mass index and waist circumference. Given the open label design and small sample size, causality cannot be inferred. fMRI analyses generated preliminary signals of change-such as increased functional activation from pre- to post-intervention in the middle frontal gyrus, angular gyrus, and supramarginal gyrus in response to processed versus unprocessed food cues. Psilocybin-assisted therapy was feasible and well-tolerated in individuals with BED. The clinical and neurobiological observations provide directions for future adequately powered trials.
Comparable studies
Other non-randomized and open-label trials on psilocybin, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Psilocybin with psychological support for treatment-resistant depression: an open-label feasibility study. Patients with moderate-to-severe, unipolar, treatment-resistant major depression | 2016 | Open-label feasibility trial | n = 12 |
| Psilocybin with psychological support for treatment-resistant depression: six-month follow-up. Patients with severe, unipolar, treatment-resistant major depression | 2017 | Open-label trial | n = 20 |
| Pilot study of the 5-HT2AR agonist psilocybin in the treatment of tobacco addiction Psychiatrically healthy nicotine-dependent smokers | 2014 | Open-label pilot study | n = 15 |
| Quality of Acute Psychedelic Experience Predicts Therapeutic Efficacy of Psilocybin for Treatment-Resistant Depression Patients with treatment-resistant depression | 2018 | Clinical trial | n = 20 |
| Safety, Tolerability, and Efficacy of Psilocybin in 9 Patients With Obsessive-Compulsive Disorder Subjects with obsessive-compulsive disorder (OCD) | 2006 | Controlled clinical trial |
Citations in the library
Cited by 1
Cites 35
- Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer: A randomized double-blind trial Journal of Psychopharmacology November 30, 2016
- Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance Psychopharmacology July 7, 2006
- Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder JAMA Psychiatry November 4, 2020
- Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin Proceedings of the National Academy of Sciences January 23, 2012
- Single-Dose Psilocybin for a Treatment-Resistant Episode of Major Depression. New England Journal of Medicine November 3, 2022
and 30 more in the library