Product Choice, Reported Symptom Relief, and Side Effect Profiles among Medical Cannabis Users: Evidence from Mobile Device Application Data

State-level analyses show dramatic benefits from the passage of medical cannabis laws from reduced deaths from opioid use to insurer cost-savings. Patient-level studies also have shown benefits from medical cannabis but typically use retrospective surveys, small sample sizes, or in the case of randomized control trials, synthetic cannabinoids or government-provided cannabis products that do not match the variety and potency of products available to medical cannabis patients in the U.S. As a result, although medical cannabis seems promising as a treatment, little is known about the extent of variation in medical cannabis products used by patients and how different types of products may differentially affect symptoms ranging from anxiety to pain. Medical cannabis can be purchased in a variety of forms from edibles to concentrates, be consumed via a variety of methods (e.g., smoking versus vaping), and chemically vary in terms of THC and CBD across plant strains and product types. We analyze the relationship between cannabis product characteristics and symptom relief across three symptom categories: anxiety, pain, and depression. In 2016, the Releaf© mobile application was launched, allowing users to track their symptom changes and side effects in relation to specific cannabis products, including form, consumption method, and THC and CBD as labeled. Data continue to be collected and as of September 2017, 3,693 users had recorded 14,664 medical cannabis “sessions” including the level of their primary symptom recorded both prior to consumption and at the end of each session as well as any side effects experienced. The preliminary results of analyzing these data indicate both substantial benefits from medical cannabis use among the Releaf© app users (a null hypothesis of no effect can be rejected with p<0.0001), but significant variation across patients and conditions, which can be partly explained by heterogeneity in forms, consumption methods, and THC/CBD levels. In particular, products that labeled as having higher levels of THC are associated with greater symptom relief. CBD alone appears to have little effect but may moderate the effect of higher levels of THC. These results suggest that studies on the effects of medical cannabis should control for the substantial variation in the products actually consumed by patients and that states with CBD-only legalization may be limiting patients to products that are not effective for symptom relief.