Using medical or recreational marijuana to ease symptoms of numerous mental health conditions doesn’t work, according to two new analyses of existing gold-standard research.
Studies on marijuana are often small and can be difficult to conduct, experts say. Still, the randomized controlled trials that made up the Lancet review are the gold-standard of research, said Dr. Deepak Cyril D’Souza, Vikram Sodhi ’92 Professor of Psychiatry and director of the Yale Center for the Science of Cannabis and Cannabinoids in New Haven, Connecticut. Read More

The JAMA Internal Medicine article highlights that while the endocannabinoid system plays a role in regulating mood and stress, there is limited high-quality clinical evidence supporting cannabis as an effective psychiatric treatment. It also emphasizes that cannabis use—especially among adolescents or individuals vulnerable to mental illness—may increase the risk of psychosis and worsen mental health outcomes, underscoring the need for caution and further research. Read More

Kansagara, D., Terry, G. E., Ayers, C. K., & D’Souza, D. C. (2026). Cannabis and Mental Health: A Review. JAMA Internal Medicine.

New research is questioning the safety of today’s legal, readily available cannabis products. In a Q&A, psychiatrist Deepak Cyril D’Souza explains the mental health risks these substances pose, especially in the adolescent brain, and what should be done about it. View Video

The February 2026 YC-SCAN2 webinar Driving While Stoned: Why It’s Complicated, featured Godfrey Pearlson, who presented a comprehensive overview of cannabis and driving impairment. His talk examined the pharmacokinetics and pharmacodynamics of THC, its behavioral effects on driving performance, and the broader public health implications of cannabis use behind the wheel. Dr. Pearlson highlighted the unique challenges in detecting cannabis-related impairment compared to alcohol, noting the limitations of current roadside sobriety testing and per se legal standards. Drawing on his research using advanced driving simulators and virtual reality paradigms, he demonstrated that THC can impair critical driving skills in subtle but meaningful ways, with effects that may persist even after blood THC levels decline. The presentation also addressed the complexity of cannabis use patterns, including variability across dosage forms and the absence of a standardized dose equivalent, and emphasized the need for continued research on issues such as edible cannabis and sex-related differences in impairment.

We are currently enrolling participants in a National Institute on Drug Abuse–funded research study examining how aging influences the short-term effects of THC, the primary active component of cannabis. As cannabis use among older adults continues to rise, this study aims to better understand both potential risks and benefits to help inform safer, evidence-based guidance.

Participation involves approximately 12 hours total, including an in-person screening visit and a single test day. On the test day, participants will receive two study doses selected from placebo, low-dose THC, or medium-dose THC, followed by brief telephone check-ins at 24 hours, 1 month, 3 months, and 6 months.

This research plays an important role in advancing our understanding of cannabis effects in older adults and supporting informed health decisions as people age.

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The Research Society on Marijuana (RSMj) Annual Scientific Meeting promotes understanding of cannabis through presentation of empirical research of determinants, correlates, consequences, contexts, and assessment of cannabis use as well as the treatment of problematic cannabis use, including cannabis use disorder. As we celebrate RSMJ's 10^th Annual Scientific meeting this year, we encourage submissions of symposia, panel, or individual abstracts to be part of this milestone meeting and help celebrate a decade of impactful contributions to cannabis research. Click to Read More

Abstract Submission Deadline: March 16, 2026

Final Deadline: March 25, 2026