A Statewide Examination of Medical Cannabis Purchasing Patterns in Arkansas Over the Three Years Immediately Following Legalization.

Introduction: The use of medical cannabis (MC) to treat a host of conditions has expanded considerably in the United States; however, precise quantitative assessments of purchasing characteristics are unknown. This study sought to characterize the trends in MC purchases, US dollars spent, and type and amount purchased by demographic and clinical characteristics. Materials and Methods: This descriptive exploratory association study examined statewide MC registry data in Arkansas linked at the person level with statewide transaction data documenting each MC purchase. MC transaction data (May 11, 2019-August 31, 2022) were assessed to identify persons who could be linked to the registry data and made at least one purchase. Individual demographic characteristics and MC qualifying conditions (QCs) were ascertained. Product types were classified into plant cannabis, cannabis extract for inhalation (vape), edibles, and others. The average daily total delta-9-tetrahydrocannabinol (THC) purchased was calculated based on the concentration and quantity purchased. Purchasing characteristics are described and demographic and clinical factors associated with THC purchased per day and dollars spent per year were estimated by ordinary least square regression and general linear models with a gamma distribution. Results: On average, 89,057 MC purchasers spent $3343 (interquartile range [IQR], $907-$4802), had 33.34 (IQR, 8.32-46.03) transaction days per year, and purchased 162.32 mg (IQR, 30.51-237.69) of THC per day. Most persons predominantly purchased plant cannabis (68.27%), followed by edibles (14.92%) and vape (11.96%). Individuals younger than 18 years of age (β=-78.23; 95% confidence interval [CI], -116.599 to -39.863), persons 70 and older (β = -122.30; 95% CI, -128.18 to -116.422), and women (β=-33.70; 95% CI, -35.95 to -31.446) purchased less THC per day than their counterparts after multivariate adjustment. The most common QCs were pain and post-traumatic stress disorder (PTSD), and compared to those with cancer, persons with pain (β = 26.30; 95% CI, 18.636-33.96) and PTSD (β = 38.34; 95% CI, 30.467-46.222) purchased more THC per day. Conclusion: The average THC purchased per person per day exceeds typically recommended daily doses for therapeutic uses, and further research is warranted to assess the safety and benefits of MC across these conditions.