The University of Pittsburgh Graduate School of Public Health has discovered a short-term decline in opioid-related emergency department visits when US states legalise recreational cannabis.  

The study, published in the journal Health Economics, found during the first two quarters after the introduction of recreational cannabis law reform, opioid-related emergency visits reduced by roughly 7.6%, particularly among men and adults aged 25-44.

While the effects dissipate after the first six months, the study showed recreational cannabis legalisation does not increase opioid-related emergency visits, suggesting cannabis is not acting as a gateway for opioids.

Speaking with Mirage News, lead author, Assistant Professor Coleman Drake from the Department of Health Policy and Management at University of Pittsburgh Graduate School of Public Health, explained the impact of the findings.

He said: “This isn’t trivial — a decline in opioid-related emergency department visits, even if only for six months, is a welcome public health development.

“But that being said, while cannabis liberalisation may offer some help in curbing the opioid epidemic, it’s likely not a panacea.”

The study sample included data from emergency department visits involving opioids between 2011 and 2017. Data was drawn from 25 states acting as controls and four which legalised recreational cannabis use during that time (California, Maine, Massachusetts and Nevada).

“A decline in opioid-related emergency department visits, even if only for six months, is a welcome public health development.”

Assistant Professor Coleman Drake

Drake added: “We can’t definitively conclude from the data why these laws are associated with a temporary downturn in opioid-related emergency department visits but, based on our findings and previous literature, we suspect that people who use opioids for pain relief are substituting with cannabis, at least temporarily.

“Cannabis can provide pain relief for persons using opioids, but [it] ultimately is not a treatment for opioid use disorder. Still, this is good news for state policymakers. States can fight the opioid epidemic by expanding access to opioid use disorder treatment and by decreasing opioid use with recreational cannabis laws.

“These policies aren’t mutually exclusive; rather, they’re both a step in the right direction.”

The study concludes that future research should continue to investigate recreational cannabis laws and opioid-related health outcomes in other states which have recently legalised cannabis over longer treatment periods, for different demographics and population groups, and for diverse health outcomes.