Acute Effects of Cannabis on Symptoms of Obsessive-Compulsive Disorder.
Little is known about the the acute effects of cannabis on symptoms of OCD in humans. Therefore, this study sought to 1) examine whether symptoms of OCD are significantly reduced after inhaling cannabis, 2) examine predictors (gender, dose, cannabis constituents, time) of these symptom changes and 3) explore potential long-term consequences of repeatedly using cannabis to self-medicate for OCD symptoms, including changes in dose and baseline symptom severity over time. Data were analyzed from the app Strainprint® which provides medical cannabis patients a means of tracking changes in symptoms as a function of different doses and strains of cannabis across time. Specifically, data were analyzed from 87 individuals self-identifying with OCD who tracked the severity of their intrusions, compulsions, andor anxiety immediately before and after 1,810 cannabis use sessions spanning a period of 31 months. Patients reported a 60% reduction in compulsions, a 49% reduction in intrusions, and a 52% reduction in anxiety from before to after inhaling cannabis. Higher concentrations of CBD and higher doses predicted larger reductions in compulsions. The number of cannabis use sessions across time predicted changes in intrusions, such that later cannabis use sessions were associated with smaller reductions in intrusions. Baseline symptom severity and dose remained fairly constant over time. The sample was self-selected, self-identified as having OCD, and there was no placebo control group. Inhaled cannabis appears to have short-term beneficial effects on symptoms of OCD. However, tolerance to the effects on intrusions may develop over time.