While many patient anecdotes have suggested that medical marijuana may be effective for chronic pain and that it could be used as an alternative to opioid pain medications, the U.S. government’s categorization of cannabis as a hardcore Schedule I narcotic with no medical use has hamstrung the ability of scientists to test that theory in clinical trials. Government-ordered studies on pot have only sought to associate it with negative externalities, and clinical trials on the safety or medical benefits of pot are effectively banned under current law.
However, pot-legal states have begun to produce volumes of data that can be analyzed by researchers, and two new scientific studies released this month in JAMA Internal Medicine have linked cannabis legalization laws with a significant reduction in opioid prescriptions filed in the state.
In the study, Association of Medical and Adult-Use Marijuana Laws With Opioid Prescribing for Medicaid Enrollees, University of Kentucky’s Hefei Wen and Emory University’s Jason Hockenberry examined “all-capture Medicaid prescription data for 2011 to 2016” between states and found that “medical marijuana laws and [recreational] adult-use marijuana laws were associated with lower opioid prescribing rates (5.88% and 6.38% lower, respectively).”
“Medical and adult-use marijuana laws have the potential to lower opioid prescribing for Medicaid enrollees, a high-risk population for chronic pain, opioid use disorder, and opioid overdose, and marijuana liberalization may serve as a component of a comprehensive package to tackle the opioid epidemic,” the study concluded.
A second study in JAMA Internal Medicine, Association Between US State Medical Cannabis Laws and Opioid Prescribing in the Medicare Part D Population by Ashley Bradford, David Bradford, and Amanda Abraham of the University of Georgia, examining “longitudinal analysis of Medicare Part D” found that “prescriptions filled for all opioids decreased by 2.11 million daily doses per year from an average of 23.08 million daily doses per year when a state instituted any medical cannabis law.”
That study also suggested that laws focused on improving medical marijuana access reduced opiate prescription rates further than other types of legalization schemes.
“The type of medical cannabis laws [MCLs] implemented in these states was important as well, with greater reductions in opioid prescriptions observed in states with more structured MCLs that increased access to medical cannabis. Prescriptions for opioids fell by 3.74 million daily doses per year (95% CI, −5.95 to −1.54) when medical cannabis dispensaries opened, but only by 1.79 million daily doses per year (95% CI, −3.36 to −0.22) when states only offered allowances for home cultivation,” read the research.
“Medical cannabis policies may be one mechanism that can encourage lower prescription opioid use and serve as a harm abatement tool in the opioid crisis,” Bradford et al concluded.
While a growing chorus of patient anecdotes have been cited by medical marijuana activists suggesting that medical cannabis has allowed them to discontinue the use of potentially-deadly opiates, the lack of scientific studies confirming this, partly due to the government’s ban on clinical research on cannabis, has often been cited by health officials in discouraging the passage of such bills.
For example, prior to the publication of these two studies, Tennessee Department of Health officials testified in a hearing on the state’s Medical Cannabis Only bill that there was not enough scientific evidence available to link medical cannabis to reduced opioid use rates or to suggest that it is effective for relief of chronic pain. On the heels of that testimony, Medical Cannabis Only died in the Tennessee Senate on Tuesday, according to The Tennessean.