Naturalistic examination of the anxiolytic effects of medical cannabis and associated gender and age differences in a Canadian cohort

Sex Differences in the Acute Effects of Oral THC: A Randomized, Placebo-Controlled, Crossover Human Laboratory Study

Rationale

Recent reports have shown increased cannabis use among women, leading to growing concerns about cannabis use disorder (CUD). Some evidence suggests a faster progression to addiction in women, known as the "telescoping effect." While there is preclinical evidence suggesting biological sex influences cannabinoid effects, human research remains scant. We investigated sex differences in the response to oral tetrahydrocannabinol (THC) in humans.

Methods

56 healthy men and women with prior exposure to cannabis but no history of CUD participated in a randomized, placebo-controlled, human laboratory study where they received a single 10 mg dose of oral THC (dronabinol). Subjective psychoactive effects were assessed by the visual analog scale of "high", psychotomimetic effects by the Clinician-Administered Dissociative Symptoms Scale and Psychotomimetic States Inventory, verbal learning and memory by Rey Auditory Verbal Learning Test (RAVLT), and physiological effects by heart rate. Outcomes were regularly measured on the test day, except for the RAVLT, which was assessed once. Peak differences from baseline were analyzed using a nonparametric method for repeated measures.

Results

Oral THC demonstrated significant dose-related effects in psychotomimetic and physiological domains, but not in RAVLT outcomes. A notable interaction between THC dose and sex emerged concerning the subjective "high" scores, with women reporting heightened sensations (p=0.05). No other significant effects of sex and THC dose interaction were observed.

Conclusion

Oral THC yields similar psychotomimetic and physiological effects across sexes, but women may experience a pronounced subjective psychoactive effect. Further research is needed to identify individual vulnerabilities and facilitate tailored interventions addressing CUD.