A new review suggests psychedelic treatments may help relieve obsessive compulsive disorder (OCD), while cannabis appears ineffective. The analysis, published in the Journal of Psychiatric Research, was led by Dr Michael Van Ameringen of McMaster University and examined alternative therapies for OCD, a condition that does not fully respond to standard treatments in up to 60% of patients.
After reviewing published studies, conference data and preliminary findings, researchers found stronger evidence supporting psychedelics, particularly psilocybin, than cannabinoids such as THC and CBD. Psilocybin appears to affect the brain’s default mode network, which is linked to rumination and intrusive thinking and is overactive in people with OCD. Cannabinoids, while influencing anxiety-related brain receptors, showed no lasting symptom relief.
Early clinical trials included in the review found that single doses of psilocybin reduced OCD symptoms compared with placebo. Researchers noted that psychedelic studies often combine medication with structured therapeutic support, which may also contribute to their effectiveness.
The authors said further research is needed but concluded that psychedelics show potential as a future treatment option for OCD, while current evidence does not support cannabis for the condition.
