Evaluating the effectiveness of psilocybin in alleviating distress among cancer patients: A systematic review.

Abstract

Psychological and existential distress is prevalent among patients with life-threatening cancer, significantly impacting their quality of life. Psilocybin-assisted therapy has shown promise in alleviating these symptoms. This systematic review aims to synthesize the evidence on the efficacy and safety of psilocybin in reducing cancer-related distress. We searched MEDLINE, APA PsycINFO, Cochrane database, Embase, and Scopus from inception to February 8, 2024, for randomized controlled trials (RCTs), open-label trials, qualitative studies, and single case reports that evaluated psilocybin for cancer-related distress. Data were extracted on study characteristics, participant demographics, psilocybin and psychotherapy intervention, outcome measures, and results. Two authors independently screened, selected, and extracted data from the studies. Cochrane Risk of Bias for RCTs and Methodological Index for Non-Randomized Studies criteria were used to evaluate study quality. This study was registered with PROSPERO (CRD42024511692). Fourteen studies met the inclusion criteria, comprising three RCTs, five open-label trials, five qualitative studies, and one single case report. Psilocybin therapy consistently showed significant reductions in depression, anxiety, and existential distress, with improvements sustained over several months. Adverse effects were generally mild and transient. This systematic review highlights the potential of psilocybin-assisted therapy as an effective treatment for reducing psychological and existential distress in cancer patients. Despite promising findings, further large-scale, well-designed RCTs are needed to confirm these results and address existing research gaps.

In the evidence

This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.

• State of the evidence: Psilocybin for end-of-life distress ↑Supports

  Across 14 studies, psilocybin therapy consistently reduced depression, anxiety, and existential distress, with improvements sustained over several months and generally mild, transient adverse effects.

  Synthesized October 22, 2026

Comparable studies

Other systematic reviews and meta-analyses on psilocybin for end-of-life distress, most cited first.