Recent rapid changes in medical cannabis policies and increases in medical use of cannabis have raised new research questions related to potential effects of medical cannabis legalization on cannabis use problems. In order to investigate such effects there is a need for screening tools that are sensitive to the fact that people may be using for medical and/or recreational purposes. This article critically assesses whether screening tools designed to measure cannabis use problems in recreational users are meaningful as measures of problems resulting from medical use.It is possible that existing cannabis problem screening tools are not equally valid across medical and recreational users, since individual screening items have different implications for recreational and medical users. For instance, items that measure use that deviates from common patterns of recreational use (use before midday and use alone) reflect normative assumptions that non-problematic recreational use will occur in contexts of parties or social gatherings. However, use before midday and alone are how people typically take medication for chronic medical health problems. There is thus a need to develop and validate criteria for problematic use in medical cannabis patients.