Medical Cannabis Dispensary Density Associated With Cannabis Use Among Young Adults

Cannabis is increasingly available in many US states through medical cannabis dispensaries, which, together with their signage, may have an effect on cannabis use among nearby youth. This study used data from 2016–2017 interviews of a cohort of 1887 young adults (aged 18–22) in southern California. Researchers investigated the association between density of dispensaries with cannabis use and positive expectancies,* taking into account neighborhood socio-economic status.

• The average number of dispensaries within 4 miles of respondents’ homes was 19; 84% of homes had ≥10 dispensaries within 4 miles.
• Higher dispensary density within 4 miles was associated with greater past-month cannabis use and more positive cannabis expectancies, compared with lower dispensary density.
• The effect of dispensaries with signage on positive cannabis expectancies was more than 6 times as large as the effect of total dispensary count.

* Measured as “the mean of four positive expectancy items (e.g. using marijuana relaxes you, helps you get away from your problems; lets you have more fun; makes sex more enjoyable) rated 1 = strongly disagree to 4 = strongly agree.”

Comments: Medical cannabis dispensaries may lead to more positive views and use of cannabis among local youth by creating perceptions of less harm and increased acceptability. Dispensary density and signage are two potential targets of regulation to consider to help reduce the possible harms associated with these outlets.

Darius A. Rastegar, MD

Reference: Shih RA, Rodriguez A, Parast L, et al. Associations between young adult marijuana outcomes and availability of medical marijuana dispensaries and storefront signage. Addiction. 2019;114:2162–2170.