No Evidence That Marijuana Reduces Illicit Opioid Use: Study

A new study conducted over 20 years finds no evidence that marijuana reduces use of illicit opioids, ABC News reports.

Researchers followed 615 people with heroin dependence between 2001 and 2022. Many of them also used marijuana. The study found that while marijuana use was very common among people who were dependent on heroin, there was no consistent relationship between the patterns of use of the two substances. There was also no evidence to suggest marijuana use reduced long-term opioid use, they wrote in the American Journal of Psychiatry.

“Our investigation shows that cannabis use remains common among this population, but it may not be an effective long term strategy for reducing opioid use,” study author Dr. Jack Wilson of the University of Sydney said in a news release. “There are claims that cannabis may help decrease opioid use or help people with opioid use disorders keep up with treatment. But it’s crucial to note those studies examine short- term impact, and focus on treatment of chronic pain and pain management, rather than levels of opioid use in other contexts.”