According to the results of a new scientific study, strong clinical evidence supports only a limited number of medical uses for cannabis, revealing a gap between popular beliefs and current scientific evidence. The research study, which was recently published in the peer-reviewed journal JAMA, is a comprehensive review of over 2,500 previous studies carried out over the period between January 2010 and September 2025.
“While many people turn to cannabis seeking relief, our review highlights significant gaps between public perception and scientific evidence regarding its effectiveness for most medical conditions,” said Dr. Michael Hsu, health sciences clinical assistant professor at the UCLA Health Department of Psychiatry and Biobehavioral Sciences, in his interview with Science Daily. “Clear guidance from clinicians is essential to support safe, evidence-based decision-making when discussing medical cannabis with their patients.”
The review findings demonstrated that robust clinical evidence supports only a small number of FDA-approved, pharmaceutical-grade cannabinoid products for specific indications, including HIV/AIDS-associated appetite loss, chemotherapy-induced nausea and vomiting, and severe pediatric epileptic syndromes. However, the available evidence remains limited for other health conditions. While more than half of medical cannabis users report using it for chronic pain, existing clinical guidelines do not support cannabis-based therapies as first-line treatments for pain.
Moreover, the review identified important safety concerns, including associations between high-potency cannabis use in adolescents and increased rates of psychotic symptoms and generalized anxiety disorder, as well as a significant prevalence of cannabis use disorder among medical users. It was also shown that daily use of inhaled or high-potency cannabis products was linked to elevated cardiovascular risks, including coronary heart disease, myocardial infarction, and stroke.
The review also advises clinicians to assess cardiovascular and psychotic risk, consider potential drug–drug interactions, and carefully weigh potential harms against benefits before recommending THC-containing products to patients. “Patients deserve honest conversations about what the science does and doesn’t tell us about medical cannabis,” Dr. Hsu added.
Importantly, the authors of the study acknowledged several limitations, including the absence of a systematic review design and formal bias assessment, the inclusion of observational studies subject to confounding, and limited generalizability of clinical trial findings across different populations and cannabis formulations. “Further research is crucial to better understand the potential benefits and risks of medical cannabis. By supporting more rigorous studies, we can provide clearer guidance and improve clinical care for patients,” said Dr. Hsu.
