The National Institute on Drug Abuse awarded a $3.3 million R01 grant to Department Vice Chair Nicole Ennis, Ph.D., and University of Florida Health Professor Sherrilene Classen, Ph.D., to support a study investigating the effects of long-term medical marijuana use — alone and with prescription opioids — on driving performance in adults 50 and older. It is the only study in the United States using an open-road driving performance task to assess medical marijuana use and aging.

The research will focus on individuals who use medical marijuana daily for 12 months or more and will analyze how that use, alongside opioid treatments for chronic pain, may affect driving. With older adults representing a rapidly growing segment of medical cannabis users, and with driving playing a key role in maintaining independence, the study aims to generate essential insights into public safety, pain management and aging.

By addressing a major gap in current evidence, the project has the potential to inform clinical guidelines and influence policy while supporting the well-being and autonomy of older adults.