Study Examines the Impact of Legal Access to Medical Cannabis on Nonmedical Prescription Opioid Use

Published on: 

A recent study found that the legalization of medical cannabis in the United States was associated with a slight decrease in nonmedical prescription opioid use.

Citing the inconclusive current research on legalization of medical cannabis and its effect on nonmedical prescription opioid (NMPO) use, a recent study examined data from the 2004–2014 National Surveys on Drug Use and Health from adults ages 21 and older with NMPO use (1). The study titled, “Association Between Legal Access to Medical Cannabis and Frequency of Non-Medical Prescription Opioid Use Among U.S. Adults,” was published in the International Journal of Mental Health and Addiction on October 30th, 2023 (1). Researchers concluded that medical cannabis laws (MCL) were associated with a slight decrease in NMPO use (2).

After analyzing the data, researchers found that as a state legalized medical cannabis, there was a 0.5 to 1.5 percentage point decrease in regular to frequent NMPO use and a 2.1 percent point increase in occasional NMPO use (2). They also found that the most significant changes came only from those who had cannabis use disorder (CUD) (1). In those cases, frequent opioid use dropped 4.9 percentage points (3).


“The association of MCL with lower frequency of NMPO use was driven by individuals with cannabis use disorder, highlighting the importance of identifying tradeoffs of cannabis legalization as an intervention to reduce opioid-related harms,” the authors stated in the abstract (1).

In the face of the rising opioid-related deaths in the US, cannabis has been explored as a possible aid to reducing opioid addiction (2).

“There might be some benefits to allowing legal access to medical cannabis in the context of opioid-related harms,” stated Hillary Samples, lead author of the study (2). “However, from a policy perspective, there are much more effective interventions to address the ongoing overdose crisis, such as increasing access to treatment for opioid addiction.”


  1. Samples, H.; Levy, N. S.; Bruzelius, E.; Segura, L. E.; Mauro, P. M.; Boustead, A. E.; Mauro, C. M.; Martins, S. S. Association between legal access to medical cannabis and frequency of non-medical prescription opioid use among U.S. adults. International Journal of Mental Health and Addiction 2023 DOI: 10.1007/s11469-023-01191-y.
  2. Swenarton, N. States with legalized medical marijuana see decline in nonmedical opioid use (accessed Nov 15, 2023).
  3. Adlin, B. Medical marijuana legalization led to reduction in frequent use of nonmedical prescription opioids, study finds (accessed Nov 15, 2023).