Does Medical Marijuana Availability Reduce Prescription of Anxiety Medication and Improve Mental Health?

Abstract: The number of drug prescriptions has increased dramatically over the past 20 years, benzodiazepine prescriptions being a prime example with an increase of 67 percent between 1996 and 2013. Benzodiazepines are usually prescribed for anxiety; a disease marijuana has been proven to have a small yet observed effect on. Simultaneously with the increase in benzodiazepine prescriptions, mental health has emerged as one of the most expensive health issues of our time estimated to cost the world $1 billion by 2030. This study uses state-level prescription data from Medicaid (1996-2018) and individual-level survey data from the Behavioral Risk Factor Surveillance Survey (2011-2018) to estimate the effect of an introduction of a medical marijuana law on benzodiazepine prescriptions and individuals’ self-reported mental health. The impact is studied with a difference-in-differences approach using the legalization of medical marijuana as the policy change. This study finds that the number of benzodiazepine prescriptions increase after the introduction of medical marijuana. This study also finds that the number of days of ill mental health decreases a medical marijuana law is introduced. Unfortunately, the results are not statistically significant at conventional levels and are therefore considered suggestive.