Systematic review · 2026
Review of 13 trials: MDMA and IV ketamine have the most PTSD evidence, results mixed
- Original title
- Efficacy and risks of psychedelics in the treatment of posttraumatic stress disorder: A systematic review.
- Authors
- Thomas JE, Dellarole A, Caballero J
- Journal
- American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, 2026
- Molecules
- MDMA, Ketamine
- Conditions
- PTSD
- Evidence grade
- Moderate
- Source
- Read the original paper
The question
Which psychedelic-type treatments have the strongest trial evidence for post-traumatic stress disorder (PTSD), and how safe are they?
What they did
The authors searched three research databases (PubMed, Web of Science and Scopus) for randomized controlled trials of psychedelic therapy for PTSD. Thirteen studies met their criteria. Six tested MDMA-assisted psychotherapy, and seven tested ketamine given by intravenous (IV) drip. The review also looked at safety reports and at who took part in the studies.
What they found
Results across the trials were mixed. Four of the six MDMA-assisted psychotherapy studies showed a statistically significant improvement in PTSD symptoms. Three of the seven IV ketamine studies showed significant benefit compared with their comparison treatments, including reduced symptoms and some lasting effect. Both treatments were described as generally well tolerated. Most studies were in mainly civilian groups; only one MDMA study and two ketamine studies focused on veterans.
The fine print
The abstract does not report how many people were included in total, the doses used, or how long participants were followed. The authors themselves flag two key problems: participants often expect to improve, and blinding is hard because people can usually tell whether they received an active psychedelic. Fewer than half of the ketamine trials showed a significant benefit. This summary is based on the abstract only.
What it means
Among psychedelic-type treatments for PTSD, MDMA-assisted psychotherapy and intravenous ketamine have the most randomized trial data so far, but the results are inconsistent and the trials have real design weaknesses.
Evidence grade: Moderate. A systematic review limited to randomized controlled trials, but the results were not pooled, the findings across studies were mixed, and only 13 studies were included.
This summary is based on the study’s published abstract.