A new review suggests psychedelic treatments, particularly psilocybin, may help reduce symptoms of obsessive-compulsive disorder (OCD), while cannabis shows little lasting benefit.
The review, led by Dr Michael Van Ameringen of McMaster University and published in the Journal of Psychiatric Research, examined evidence for alternative OCD treatments. It found stronger support for psychedelics than for cannabinoids such as THC and CBD, which appear to offer only short-term relief.
Researchers believe the difference lies in how the substances affect the brain. Psilocybin reduces activity in the default mode network, which is linked to rumination and obsessive thinking in OCD, while cannabis mainly targets receptors related to anxiety and compulsions without producing durable changes.
Preliminary clinical trials included in the review showed that even a single dose of psilocybin could significantly improve OCD symptoms compared with placebo. Researchers caution that further controlled studies are needed, but say the findings offer hope for patients who do not respond to existing treatments.
