Study Finds Buprenorphine May Reduce Cannabis Use in Patients Treated for Opioid Use Disorder
Most people with a substance use disorder concurrently use multiple drugs. Prior research estimates that approximately a quarter of individuals with an opioid use disorder (OUD) also use cannabis. While both buprenorphine and naltrexone are FDA-approved medications for the treatment of OUD, their specific impact on cannabis use has historically remained unknown.
To explore this relationship, researchers sought to determine whether either extended-release naltrexone or sublingual buprenorphine affected cannabis use among treatment-seeking individuals diagnosed with OUD. This was accomplished through a secondary analysis of data collected from the X:BOT randomized controlled trial, which was originally designed to evaluate the comparative effectiveness of these two medications for OUD treatment. The X:BOT Trial included 569 participants who were randomly assigned to receive one of the OUD treatment medications and were followed for 24 weeks. At the start of the study, 42% of all participants reported using cannabis.
The analysis revealed a significant effect: individuals receiving buprenorphine were 39% less likely to use cannabis across all observed time points than those receiving naltrexone. This finding is novel, as no previous clinical research had examined this specific cross-substance interaction.
Researchers have proposed two primary hypotheses for this outcome:
The Buprenorphine Mechanism: As a partial opioid agonist, buprenorphine's specific activity at the opioid receptors may alleviate underlying anxiety or mood disorders. By addressing these co-occurring symptoms, it may mitigate an individual's perceived need to self-medicate with cannabis.
The Naltrexone Mechanism: Conversely, because naltrexone acts as a full opioid antagonist that completely blocks opioid receptors, individuals in this group may turn to cannabis as a substitute to achieve a desired psychoactive effect.
While these findings are promising, the study notes several limitations. Most notably, the primary clinical trial was not originally designed to test medications for cannabis cessation, meaning further targeted research is required. Nevertheless, for patients seeking treatment for OUD who also consume cannabis, selecting buprenorphine as a primary intervention may offer a dual advantage by simultaneously helping to address the use of both drugs.
The Study
Shulman, M., Choo, T. H., Ohrtman, K., Pavlicova, M., Rotrosen, J., & Nunes, E. V. (2025). Effects of randomization to buprenorphine or naltrexone for OUD on cannabis use outcomes: A secondary analysis of the X:BOT trial. Drug and alcohol dependence, 268, 112550. https://doi.org/10.1016/j.drugalcdep.2025.112550
