New Study: Cannabis May Reduce Illicit Opioid Use For Those With Chronic Pain

How does cannabis use influence the use of illicit opioids to manage pain? That’s the question at the heart of a just-published study in a special issue of “PLOS Medicine” that focuses on substance use, misuse and dependence. For medical researchers, caregivers and patients, the need for an alternative to opioid painkillers is an urgent one. Opioid-related deaths are still on the rise across the United States and Canada, fueled by the emergence of synthetic opioids like fentanyl and a trend of over-prescribing pharmaceutical opioids. And the role cannabis might play in reducing opioid dependence and abuse is still little-understood.

But the new “PLOS Medicine” study, “Frequency of cannabis and illicit opioid use among people who use drugs and report chronic pain,” provides an important perspective on the question by researching individual-level data—something many current studies lack. Following more than 1,100 individuals over a 30-month period, researchers aimed to investigate associations between how often people with chronic pain use cannabis and how often they turn to illicit opioids. And what they found could change the way we look at cannabis and the opioid epidemic in dramatic ways.

Daily Cannabis Use Significantly Lowers Odds of Daily Illicit Opioid Use

Doctors over-prescribing opioid painkillers is undeniably a contributing factor in the opioid epidemic. But what about people suffering from chronic pain who don’t have adequate access to the healthcare system? For such marginalized groups, under-treated—or untreated—pain can promote a higher risk of substance use and abuse, including the use of illicit opioids like heroin or fentanyl and counterfeit pharmaceutical drugs.

Yet people without access to the healthcare system can also turn to cannabis as a pain management strategy. Given the research that already supports using cannabis as a possible opioid substitute, and studies that have identified how cannabis-based medications can treat chronic pain, alongside the simple fact that cannabis doesn’t pose a fatal overdose risk, this strategy is both a safer and more desirable way to manage untreated or under-treated pain.

In fact, multiple studies show how states and provinces that provide access to legal cannabis are observing population-level reductions in opioid use, dependance, abuse and fatal overdoses. At the same time, one recent study has countered that narrative, suggesting that for patients with long-term opioid prescriptions, cannabis use doesn’t produce meaningful reductions in opioid prescriptions or doses. To help understand these divergent findings, researchers drilled down to individual-level data to analyze how cannabis use is related to illicit opioid use specifically.

Study Highlights How Cannabis Can Replace and Reduce Opioid Use

What they found is eye-opening. According to the new study, people who used cannabis daily were 50 percent less likely to use illicit opioids every day. Furthermore, people with chronic pain who only used cannabis occasionally were no more or less likely to use illicit opioids than patients who used no cannabis at all. The study also concluded that daily cannabis users were more likely than occasional or non-users to report therapeutic reasons for their cannabis consumption: pain, nausea, sleep and stress.

“We observed an independent negative association between frequent cannabis use and frequent illicit opioid use among people who use drugs with chronic pain,” the study concluded.

To reach their conclusions, researchers used data sets from 2 large studies of people who use drugs (PWUD) in Vancouver, Canada. The data sets total 1,152 PWUD, representing 424 women and a median age of 49.3 years. Of those individuals, 455 (40 percent) reported using illicit opioids daily, while 410 (36 percent) reported daily cannabis use at least once during a 6-month followup interview.

Using statistical methods that adjusted for demographic factors, substance use and health-related factors, researchers found that daily cannabis use was associated with a 50 percent lower chance of daily illicit opioid use.

Researchers’ findings have a couple of important implications. First, they suggest that increasing the availability of legal cannabis is benefitting people with chronic pain who are turning to cannabis to either alleviate pain and/or reduce their opioid use. Second, they add weight to claims that cannabis can serve as a substitute for illicit opioid use and a companion treatment to reduce prescription opioid use.