People who inject drugs use cannabis for pain relief, emotional support, and as an opioid substitute | Research

The takeaway

Among 387 people who inject drugs and use cannabis, the most common motivations were getting high, physical pain relief, emotional support, and reducing opioid use, with pain relief strongly linked to using cannabis as an opioid substitute.

Harm reduction advocates, substance use treatment providers, public health researchers

Pain relief motivation strongly predicted using cannabis as an opioid substitute

What the researchers found

Cannabis use for physical pain relief was associated with higher odds of using cannabis as an opioid substitute. Cannabis for emotional problems was associated with depression diagnosis. Cannabis as an opioid substitute was linked to non-prescribed methadone use.

Why it matters

If people who inject drugs are already using cannabis as a self-directed harm reduction strategy, formalized programs could potentially leverage this behavior to reduce opioid use and overdose risk.

The numbers in context

387 people who inject drugs; most common motivations: getting high, pain relief, emotional problems, opioid reduction; pain relief associated with opioid substitution; depression associated with emotional use motivation

How the study worked

Analysis of 6-month follow-up data from 387 people who inject drugs and reported past-month cannabis use, recruited from Los Angeles and San Francisco (2016-2018). Multivariable logistic regression examined motivations.

What this study cannot tell us

Cross-sectional design, self-reported motivations, specific to people who inject drugs in two California cities, cannot determine whether cannabis actually reduces opioid use or harm.

How to read the evidence

Cross-sectional survey of a specific high-risk population in two California cities

When this study was published

Published in 2021 using 2016-2018 data from Los Angeles and San Francisco.

The bigger picture

These findings align with a growing body of evidence that cannabis may serve as a harm reduction tool in opioid-using populations, though the direction of causality is unclear.

Questions still open

Would providing formal access to cannabis products reduce opioid use in this population? Are cannabis-using people who inject drugs at lower risk for overdose? What role should cannabis play in harm reduction programs?

Common questions

Are people who inject drugs using cannabis to reduce opioid use?

Yes. Among 387 cannabis-using people who inject drugs, reducing opioid use was a common motivation, and those who used cannabis for pain relief were most likely to also use it as an opioid substitute.

Could cannabis be part of harm reduction for opioid users?

The self-reported motivations suggest cannabis already functions as informal harm reduction in this population. However, clinical studies are needed to determine whether this actually reduces opioid use or improves outcomes.

Read the original research

Factors associated with health-related cannabis use intentions among a community sample of people who inject drugs in Los Angeles and San Francisco, CA 2016 to 2018.

Drug and alcohol dependence, 219, 108421

View on PubMed ↗Publisher’s paper ↗

Citation

Ceasar, Rachel Carmen; Kral, Alex H; Simpson, Kelsey; Wenger, Lynn; Goldshear, Jesse L; Bluthenthal, Ricky N. (2021). Factors associated with health-related cannabis use intentions among a community sample of people who inject drugs in Los Angeles and San Francisco, CA 2016 to 2018.. Drug and alcohol dependence, 219, 108421. https://doi.org/10.1016/j.drugalcdep.2020.108421