Cannabis as a substitute for alcohol and other drugs: A dispensary-based survey of substitution effect in Canadian medical cannabis patients

Background: This article examines the subjective impact of medical cannabis on the use of both licit and illicit substances via self-report from 404 medical cannabis patients recruited from four dispensaries in British Columbia, Canada. The aim of this study is to examine a phenomenon called substitution effect, in which the use of one product or substance is influenced by the use or availability of another. Methods: Researchers teamed with staff representatives from four medical cannabis dispensaries located in British Columbia, Canada to gather demographic data of patient-participants as well as information on past and present cannabis, alcohol and substance use. A 44-question survey was used to anonymously gather data on the self-reported impact of medical cannabis on the use of other substances. Results: Over 41% state that they use cannabis as a substitute for alcohol (n = 158), 36.1% use cannabis as a substitute for illicit substances (n = 137), and 67.8% use cannabis as a substitute for prescription drugs (n = 259). The three main reasons cited for cannabis-related substitution are "less withdrawal" (67.7%), "fewer side-effects" (60.4%), and "better symptom management" suggesting that many patients may have already identified cannabis as an effective and potentially safer adjunct or alternative to their prescription drug regimen. Discussion: With 75.5% (n = 305) of respondents citing that they substitute cannabis for at least one other substance, and in consideration of the growing number of studies with similar findings and the credible biological mechanisms behind these results, randomized clinical trials on cannabis substitution for problematic substance use appear justified.