Objective: Management of chronic pain is one of the most common reasons given by individuals seeking medical cannabis. However, very little information exists about the concurrent use of cannabis and prescription pain medication (PPM). This study fills this gap in knowledge by systematically comparing medical cannabis users who use or do not use PPM, with an emphasis on understanding whether concurrent use of cannabis and PPM is associated with more serious forms of alcohol and other drug involvement. Method: Data from this study were collected from a medical cannabis clinic in southwestern Michigan (N = 273). Systematic comparisons were made on measures of sociodemographics,...