Underground small-group therapy of treatment-resistant depression and complex post-traumatic stress disorder (C-PTSD) with psilocybin—A retrospective case study
March 10, 2023 preprint DOI: 10.31234/osf.io/t6k9b (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case report |
|---|---|
| Sample size | 1 |
| Population | A woman in her early forties with early complex trauma and treatment-resistant depression |
| Interventions | breathing exercises cold exposure physical exercises music psilocybin mushrooms |
| Duration | 1.5 years of intervention, 2.5-year follow-up |
| Topics | Depression Psilocybin Psychedelic-assisted therapy PTSD |
| Keywords | Psilocybin therapy Mushroom therapy Entheogenic treatment Hallucinogen therapy Psychedelic medicine Multi-dose Extended strategy Mixed-method Small-group sessions Depression remission Severe depression treatment Chronic depression healing Mood disorder therapy Psychiatric recovery Mental health intervention Trauma processing Trauma-related dissociation Psychological trauma Dissociative disorders Past experiences processing Clinical case report Case study Single-patient study Clinical evidence |
| Citations | 9 |
| Key findings | After six psilocybin sessions over 1.5 years, the woman achieved sustained remission of her treatment-resistant depression, with psilocybin appearing to produce an anti-dissociative effect that facilitated trauma processing. |
Abstract
While a relatively large body of research exists on many aspects of psychedelic therapy, articles describing a complete, successful treatment process are rarely found. This article therefore presents a case of a woman in her early forties with early complex trauma due to domestic violence, sexual abuse and poverty in her childhood, resulting in approximately three decades of treatment resistant depression. Antidepressive medications did not alleviate her depression but resulted in adverse effects and an eventual discontinuation of the medications. Eventually the woman resorted to 'mixed-method' underground small-group sessions that utilized breathing exercises, cold exposure, physical exercises, music, and psilocybin mushrooms. Psilocybin appeared to interrupt trauma-related dissociation, producing an 'anti-dissociative' effect, allowing the woman to re-experience, in a controlled setting, dissociated physical sensations produced by earlier overwhelming events. After a period of approximately 1.5 years, during which time she had six psilocybin sessions, either individually, in the small group, or with friends, she achieved a remission of her depression. A follow-up interview 2.5 years later indicated permanence of the result. Information was acquired from semi-structured retrospective interviews with a total duration of approximately eight hours. This case study may facilitate an improved understanding of the requirements for and the process of alleviating or resolving treatment-resistant depression with psychedelics. Recent clinical trials have utilized one or two doses of psilocybin. This case illustrates the need for adopting a multi-dose strategy over an extended period of time in order to achieve remission.
Comparable studies
Other case reports and case series on PTSD, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Combining Cognitive-Behavioral Conjoint Therapy for PTSD with 3,4-Methylenedioxymethamphetamine (MDMA): A Case Example. One couple with PTSD and a severe trauma history, participating in a pilot trial... | 2019 | Case study | n = 2 |
| Effects of intranasal (S)-ketamine on Veterans with co-morbid treatment-resistant depression and PTSD: A retrospective case series Veterans with co-morbid depression and PTSD | 2022 | Retrospective case series | n = 35 |
| Repeated oral esketamine in patients with treatment resistant depression and comorbid posttraumatic stress disorder Patients with treatment-resistant depression and comorbid PTSD | 2023 | Case series | n = 5 |
| Treatment of nightmares in the context of posttraumatic stress disorder A client with chronic, severe posttraumatic stress disorder (PTSD) | 2010 | Case study | n = 1 |
| 5-MeO-DMT for post-traumatic stress disorder: a real-world longitudinal case study 23-year-old female with chronic refractory PTSD | 2023 | Case study | n = 1 |
Citations in the library
Cited by 9
- Self-treatment of psychosis and complex post-traumatic stress disorder with LSD and DMT—A retrospective case study Psychiatry Research Case Reports July 15, 2022
- The effects of psilocybin on psychological distress in cancer patients: a systematic review and meta-analysis BMC Psychology January 2, 2026
- Hormonal Influences on Psilocybin Responsivity Across the Female Lifespan: Toward Personalized Psychedelic-Assisted Therapy Psychoactives November 2, 2025
- 5-MeO-DMT in the complete resolution of the consequences of chronic, severe sexual abuse in early childhood—a retrospective case study June 7, 2024
- Impact of Formulation Variables on the Quality Attributes of Psilocybin-Loaded Oral Thin Films for Early-Phase Development Journal of Drug Delivery Science and Technology March 1, 2026
and 4 more in the library
Cites 19
- Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder JAMA Psychiatry November 4, 2020
- Psilocybin-assisted treatment for alcohol dependence: A proof-of-concept study Journal of Psychopharmacology January 13, 2015
- Quality of Acute Psychedelic Experience Predicts Therapeutic Efficacy of Psilocybin for Treatment-Resistant Depression Frontiers in Pharmacology January 17, 2018
- Psilocybin for treatment-resistant depression: fMRI-measured brain mechanisms. Scientific Reports October 13, 2017
- Psilocybin-occasioned mystical-type experience in combination with meditation and other spiritual practices produces enduring positive changes in psychological functioning and in trait measures of prosocial attitudes and behaviors Journal of Psychopharmacology October 11, 2017
and 14 more in the library