A new study from the American Medical Association shows that when states legalize medical marijuana, opioid prescriptions and use go down by a large amount among some cancer patients.
The study looked at insurance claims from 38,189 people who had just been told they had cancer. It found that legalizing medical cannabis between 2012 and 2017 was linked to a “relative reduction of 5.5% to 19.2%” in the number of opioid prescriptions.
The cross-sectional analysis looked at opioid prescribing in a total of 34 states. Researchers at Weill Medical College of Cornell University, Harvard University, University of Texas, and Albert Einstein College of Medicine also looked at how the number of dispensaries affected opioid prescribing in a different way.
They found that “in general, medical marijuana legalization with dispensary allowances was associated with a larger reduction in the rate of 1 or more opioid days.” This was especially true for people who had just been diagnosed with breast cancer.
According to a recent report by JAMA Network, the results suggest that some adult cancer patients who were being treated with opioids used less of them after medical marijuana was made legal.
There are several ways this could happen. Since medical marijuana is legal, oncologists and other doctors may have given out less opioids. Medical marijuana legalization may have also led to less demand for opioids from people who use marijuana to treat their own pain and from people who didn’t want to complain about pain because they thought marijuana was an alternative to opioids.
Without information on how doctors treat patients or how patients use medical marijuana, it is hard to say what the observed associations mean. Recent practitioner surveys found that a lot of patients ask their doctors about medical marijuana, but doctors don’t know much about it and aren’t always willing to prescribe or recommend it.