June 13, 2019
A number of people who advocated for the legalization of marijuana for medicinal purposes made the not-unreasonable argument that the effect of such laws would be a reduction in opioid use.
According to this article in The Atlantic, however, it didn’t quite work out that way.
Nearly five years ago, a study on medical cannabis concluded that the 13 states that had legalized medical marijuana had a 25 percent lower rate of opioid mortality than those that hadn’t.
But a recent study has come to the exact opposite conclusion. While the study confirmed the previous study’s findings (from 1999 to 2010, the introduction of medical-marijuana laws was associated with a decline in opioid-overdose deaths), when researchers included states that introduced laws between 2010 and 2017, the direction of the relationship reversed. Instead of a reduction in opioid overdoses, medical marijuana was associated with a 23 percent increase in overdose deaths.
The conclusion? There is probably no causal relationship between the two.