In a review of previous studies, McMaster University researchers observe a stronger signal for psilocybin as a treatment for obsessive-compulsive disorder than cannabinoids.

Obsessive-compulsive disorder involves persistent, intrusive thoughts and repetitive mental or physical behaviors, and requires long-term treatment to alleviate symptoms. The ethology of the disorder appears complex, involving multiple biological pathways. Imbalances in central serotonin, dopamine, and glutamate activities are widely thought to play a causative role, placing neurochemistry at the center of many treatment strategies.

First-line treatment includes selective serotonin reuptake inhibitors and cognitive behavioral therapy using exposure and response prevention. Roughly 40–60% of patients remain unresponsive to psychotherapy or pharmacotherapy, alone or combined, placing many people in the category of treatment-resistant OCD.

Northeastern University researchers have made a breakthrough drug discovery, developing the first synthetic endogenous cannabinoid compound, with repercussions for new therapeutics from pain and inflammation to cancer.

Spyros P. Nikas, an associate research professor in Northeastern’s Center for Drug Discovery, says that the discovery hinges on the distinction between two different kinds of cannabinoid chemicals, endogenous and exogenous. Exogenous cannabinoids are those produced outside the human body, like THC or CBD, both derived from the cannabis plant and present in marijuana.

Our own bodies, however, are also producing cannabinoids all the time. Called endogenous cannabinoids —or just “endocannabinoids”—these chemicals “modulate a wide range of physiological and pathophysiological responses,” Nikas says, processes that include mood, inflammation and even neurodegenerative disorders like Alzheimer’s and Parkinson’s. The research is published in the Journal of Medicinal Chemistry.