Exploring the effects of cannabidiol on pain sensitivity using quantitative sensory testing among individuals receiving methadone or buprenorphine for opioid use disorder: an open-label, proof-of-concept study

While medications for opioid use disorder (MOUD) effectively treat opioid use disorder (OUD), concurrent pain management remains challenging. Cannabidiol (CBD) shows promise in both pain management and OUD treatment. This open-label, proof-of-concept study aimed to evaluate the safety and tolerability of cannabidiol (CBD) and explore its utility for pain sensitivity using quantitative sensory testing (QST) among individuals with co-occurring OUD and chronic pain. Seven individuals with OUD receiving methadone or buprenorphine and experiencing chronic pain completed three test sessions with ascending oral CBD doses (400 mg, 800 mg, 1200 mg). QST analyses for pain sensitivity showed no significant main effects of CBD dose or time but revealed a significant MOUD x CBD dose interaction for heat pain threshold and tolerance. Post-hoc comparisons indicated that participants receiving buprenorphine exhibited significantly higher heat threshold (400 mg) and heat tolerance (800 mg) compared to those receiving methadone. Descriptively, the 400 mg CBD dose was associated with the most favorable pain response patterns across several QST measures in the buprenorphine group. CBD was well-tolerated across all doses; no serious adverse events, changes in subjective effects, or adverse cognitive effects on verbal memory were reported. In conclusion, this pilot study offers preliminary indications that CBD's impact on pain sensitivity varies by dose and MOUD type, notably with potential benefits at 400 mg for individuals on buprenorphine. Coupled with its demonstrated safety and tolerability, these findings support future larger, placebo-controlled randomized trials to confirm CBD's therapeutic utility for pain in this population.