Legalizing Cannabis Reduces Opioid Perscriptions, Study Shows

Jan 26, 2023 at 10:29 am
Legalizing Cannabis Reduces Opioid Perscriptions, Study Shows
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This story was originally published in LEO Weekly's sister publication the Riverfront Times in St. Louis.

States that have legalized adult-use marijuana have a significant reduction pharmacy-based codeine prescriptions a new study shows. The study was published January 19 in the Journal of Health Economics.

Using data from the federal Drug Enforcement Administration which tracks controlled substances across the U.S., the study looked at 11 states that had legalized adult-use cannabis between 2010 and 2019. Researchers found that there was a 26 percent reduction in “pharmacy-based distribution of codeine” and after four years many states experienced as much as a 37 percent reduction.

Codeine is an opioid, and prescription opioids contribute to more than 10,000 overdose U.S. deaths annually. But codeine is just one such opioid prescription, and the study found that marijuana legalization had “minimal impact on distribution of other opioids such as oxycodone, hydrocodone, and morphine in any setting.” Plus, marijuana legalization did not have an impact on hospital-distribution of codeine.

Researchers speculated that the pharmacy-based reduction is because codeine is a weaker opioid with a high potential for addiction. Since cannabis, like codeine, can help reduce chronic pain, its legalization can shift consumers away from opioid misuse and towards cannabis.

“A reduction in the misuse of opioids will save lives,” says Shyam Raman, a doctoral candidate at Cornell University and lead author of the study. “Our research indicated that recreational cannabis laws substantially reduce distribution of codeine to pharmacies, an overlooked potential benefit to legalizing recreational cannabis use.”

The study further confirms what other studies have found, that given the option, patients will often substitute marijuana for opioid painkillers. In 2019, the Journal of Pain came to this conclusion using online surveys submitted by adult cannabis users. When survey respondents were asked why they’d made the change, they sited fewer adverse side effects and more success managing symptoms.

Harm Reduction Journal published a similar study in 2019 that was based on a survey of 2,000 Canadian adult-use marijuana users.

This study is unique since it uses DEA data instead of survey respondents. The DEA data shows endpoint distribution of controlled substances — so whether the drugs ended up at a pharmacy, a hospital, a specialist, or a narcotic treatment program. The authors believe this is the first study of its kind to use the DEA data in this way.