Legalization of Smokable Medical Cannabis and Changes in the Dispensed Amount of Δ-9 Tetrahydrocannabinol Per Patient.

Abstract

Introduction: Florida's medical cannabis (marijuana) program is among the largest in the United States. Smokable cannabis forms were not legally available in this program until 2019, and five years after other forms of cannabis were available. This study assessed changes in Δ-9 tetrahydrocannabinol (THC) dispensed per patient following legalization of smokable cannabis in Florida. Materials and Methods: This quasi-experimental study used data from the Florida Department of Health Office of Medical Marijuana Use Reports on THC dispensing from April 6, 2018, through March 13, 2020. Certified medical cannabis user during the study period was included. The exposure was the dispensed amount of THC from legalized smokable forms of medical cannabis (statute identified as SB182), effective as of March 2019. Changes in level and trend of average milligram (mg) of dispensed THC per certified patient with 95% confidence intervals (CIs), before and after SB182, were calculated by fitting a generalized least squares linear model and allowing a 17-week phase-in period. Results: The number of certified patients increased by 24.8% from 197,107 (March 22, 2019) to 246,079 (July 19, 2019) and to 325,868 by March 13, 2020. Assuming that a 20% THC concentration in smokable products, there was a significant level increase in the mean weekly dispensed THC amount per certified patient of 138.45 mg (95% CI: 102.69-174.20), translating to a 42.18% increase (95% CI: 33.14-50.28), from the pre-policy period. We noted a continuous increase of 5.62 mg per certified patient per week (95% CI: 4.35-6.89) throughout the 35 weeks following the policy, when compared with the period before. Assuming 10% THC concentration in smokable products, we observed a significant level increase of 35.10 mg (95% CI: 5.31-64.88), corresponding to an increase of 10.70% (95% CI: 1.70-18.89), and a trend increase of 2.23 mg per certified patient per week (95% CI: 1.18-3.29). Discussion: The expansion of the Florida medical cannabis program to include smokable cannabis forms was associated with a significant increase in the mean amount of weekly dispensed THC per certified patient. Findings suggest that the dispensed amount of THC after legalization of smokable medical cannabis far exceeds the maximum recommended daily dose, based on extrapolation from oral cannabis product dosing recommendations from one expert consensus statement, raising questions about the safety, and need for consumer education.