Montreal, Canada: The adoption of state laws regulating the sale of cannabis to adults is strongly associated with reductions in the use of prescription opioids, according to a review of longitudinal studies published in the journal Frontiers in Psychiatry.
Canadian investigators reviewed data from 32 longitudinal studies evaluating public health outcomes in states that legalized adult-use cannabis sales compared to jurisdictions that did not.
Consistent with prior analyses, researchers identified “robust associations” between the enactment of adult-use legalization and decreases in the public’s use of prescription opioids.
“Most research articles included on this topic were evaluated as having high-quality evidence,” they acknowledged. “As such, the evidence is sufficient to establish a potentially beneficial association between recreational marijuana legislation and prescription opioid patterns.”
Though researchers acknowledged “moderate increases” in adults’ past-month use of cannabis following legalization, they identified “no increase in [use among] adolescents or young adults.” They also failed to identify any uptick in incidences of problematic marijuana use among young people – a finding consistent with prior data.
Authors reported inconsistent findings with respect to the potential impact of adult-use legalization on traffic safety or upon the public’s use of alcohol. They identified no increases in the public’s use of tobacco following marijuana legalization, and they failed to draw any conclusions regarding legalization’s impact on either crime rates or suicides due to a lack of sufficient data.
Full text of the study, “The clouded debate: A systematic review of comparative longitudinal studies examining the impact of recreational cannabis legalization on key public health outcomes,” appears in Frontiers in Psychiatry. Additional information is available from the NORML Fact Sheet, ‘Relationship Between Marijuana and Opioids.’