Researchers and policymakers are interested in recent research that suggests marijuana may reduce opioid use disorder and overdose deaths. The theory advanced by advocates [but not by those who treat abuse disorders and addiction] is that marijuana has been shown to relieve pain and those suffering from pain prefer it to opioids.
[Editor’s note: The National Academies of Sciences, Engineering, and Medicine’s 2017 review of marijuana research finds substantial evidence that marijuana relieves certain kinds of pain although most of that evidence comes from nabiximols, a 50/50 mix of extracted and purified THC and CBD, not the whole plant.]
Two ecological analyses show deaths from opioid overdoses are 25 percent lower in states that have legalized marijuana for medical use than those that have not. Significant reductions in opioid prescriptions in medical marijuana states also have been reported. However, these studies look at state-level data.
No prospective epidemiological or clinical studies have shown that marijuana use reduces opioid use. This study fills that critical gap in knowledge. Researchers assessed prospective associations between marijuana use in 2001-2002 among 35,000 people in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) and nonprescription opioid use and use disorders in a NESARC follow-up study three years later (2004-2005).
The researchers find that marijuana use “appears to increase rather than decrease the risk of developing nonmedical prescription opioid use and opioid use disorder.” They note their findings support the possibility that the increase in marijuana use since 2001-2002 may have worsened the opioid crisis facing the nation today.