Military veterans with post-traumatic stress disorder who got no relief from conventional treatments went into remission following treatment with the psychedelic drug psilocybin in a small U.S. pilot study, researchers say.
In the United States, psilocybin and almost all other psychedelic drugs are controlled substances in the same class as heroin or ecstasy, meaning they are deemed to have no medical use and high risk for abuse.
In April, President Donald Trump signed an executive order directing health regulators to speed reviews of psychedelic treatments and increase federal funding for research into their use.
The current early-stage study - the first to formally test the treatment in veterans with PTSD - adds to earlier evidence suggesting a benefit from psilocybin, the active ingredient in magic mushrooms, said study leader Alan Davis of The Ohio State University College of Social Work.
It was designed to test safety and cannot prove that psilocybin is an effective treatment for PTSD, but does signal the value of further testing in larger groups of patients.
Nine of the 12 veterans in the trial no longer met the criteria for PTSD a month after the treatment, according to a report in Communications Medicine.
“For a population with severe treatment-resistant PTSD, these results are striking,” study coauthor Stacey Armstrong, also of Ohio State University, said in a statement.
The 11-week trial period combined eight hours of psychotherapy followed by two doses of synthetic psilocybin given two to three weeks apart. Six to eight more hours of integrative therapy followed the drug treatment.
The most common side effect was a mild headache after taking psilocybin.
“The ability for (patients) to go back and to revisit really difficult events that happened to them and to find a new way of understanding them and a new way of moving forward in their life has really been exciting,” Davis said in a statement.
Two of the three veterans who were not in remission at one month showed small decreases in PTSD symptoms, while the third person only had negligible decreases in symptoms.
In Australia, psilocybin is authorized for treatment-resistant depression. Switzerland also allows limited use of psilocybin psychotherapy.
The PTSD researchers say they hope to secure funding to follow up with a larger randomized, controlled clinical trial.
In the meantime, they will continue to assess the treatment’s effectiveness up to six months after the current trial, as well as biological changes and effects on other PTSD-related problems like sleep disorders and substance use, they said.
