Studies Claiming Marijuana Legalization Reduces Opioid Deaths Should Not Be Trusted

The marijuana industry has made a list of claims finding legalization to be an unmitigated success (and why not, their profits depend on it!). One such claim rests on the idea that greater access to marijuana leads to a reduction in opioid problems. This was first presented in a 2014 study claiming a 25% reduction in opioid deaths in states with medical marijuana-and it has since been emblazoned across billboards nationwide.

More recently, a study published in Economic Inquiry purports to show marijuana legalization is responsible for a 21% reduction in opiate mortality. These studies represent outliers, however, and suffer from major methodological weaknesses.

First, the 2014 study has been updated in 2019 by Stanford researchers. They found when the study was extended to include states legalizing marijuana between 2010 and 2017, marijuana legalization was associated with a 25% increase in opioid fatalities.

The Economic Inquiry study ignores data from half of the country and fails to control for numerous other possible explainers/factors.
What’s more, according to the National Survey on Drug Use and Health, medical marijuana users make up around 2.5% of the population of any given state. Knowing this, it is logically unfeasible that such a small population is responsible for a whopping 25% reduction in opiate mortality.

Furthermore, another 2019 study, this time in Substance Use and Addiction, a JAMA-related publication, concluded “medical marijuana law enactment was not associated with a reduction in individual-level non-medical opioid abuse, contradicting the hypothesis that people would substitute marijuana for prescription opioids.”

In the 2019 Stanford study, the lead author concluded, “Is passing medical cannabis legalization a good strategy to prevent opioid overdose death, and I think our study gives pretty good evidence, that it’s not.”

Such studies present legitimate threats to viable and well-established methods of facilitating recovery among victims of opioid abuse. The data, when misinterpreted, has the potential to downplay the importance of access to medically assisted treatment, as well as the role of naloxone in overdose prevention.

Dr. Shover, of the Stanford study, has stated, “If patients are given, are encouraged, or driven to try medical cannabis, instead of therapy for opioid use disorder that we do have evidence for, my concern is just that it won’t be as effective and that will be worse for patients and their families.”

What’s more, readers of these reports, who do not understand the statistical nuances at play, may accept the reports as settled science.

Given that research has shown marijuana users are in fact more than twice as likely to abuse prescription opioids, more likely to require higher doses of opiate medications for pain, and more likely to use marijuana in conjunction with opioids, we must stop perpetuating the false notion that marijuana is an answer to opioid abuse.

In the midst of a true addiction epidemic, the risks are too great.