In a 24-week randomized trial of opioid agonist therapy for prescription opioid use disorder, cannabis use had no significant effect on opioid use, craving, or withdrawal symptoms.
Read this if you are in opioid treatment and use cannabis, or if you work in addiction medicine and set treatment policies around cannabis use.
BF < 0.3Bayesian analysis actively supports no effect of cannabis on opioid treatment outcomes
What the researchers found
Among 272 participants with prescription-type opioid use disorder randomized to buprenorphine/naloxone or methadone, cannabis use (mean 2.3 days/week) was not significantly associated with opioid use, craving, or withdrawal symptoms across the 24-week study. Bayesian analysis strongly supported the null hypothesis (all Bayes factors <0.3), meaning the data actively favor the conclusion that cannabis has no meaningful effect on these opioid treatment outcomes.
Why it matters
Many treatment programs restrict or penalize cannabis use among patients in opioid treatment. This trial provides rigorous evidence from a pragmatic RCT that cannabis use does not worsen opioid treatment outcomes — information relevant to treatment policy.
The numbers in context
- 272 participants: 138 BUP/NX, 134 methadone
- Mean cannabis use: 2.3 days/week
- Cannabis-opioid use association: aβ=-0.06±0.04, p=0.15
- Cannabis-craving: aβ=-0.05±0.08, p=0.49
- Cannabis-withdrawal: aβ=0.09±0.1, p=0.36
- All Bayes factors <0.3 (supporting null)
- BUP/NX mean max dose: 17.3 mg/day
- Methadone mean max dose: 67.7 mg/day
How the study worked
Exploratory analysis from OPTIMA, a multi-center, pragmatic, 24-week, open-label RCT. Cannabis and opioid use measured biweekly via timeline follow-back. Craving measured at multiple timepoints. Withdrawal measured at weeks 2, 4, 6. Repeated measures generalized linear mixed models with Bayesian analysis.
Who was studied
272 adults with prescription-type opioid use disorder in a multi-center Canadian RCT
What this study cannot tell us
Exploratory secondary analysis of a trial not designed to test cannabis effects. Self-reported cannabis use. Participants had prescription-type OUD which may differ from heroin use disorder. Open-label design for the primary treatment comparison.
How to read the evidence
Exploratory analysis from a multi-center pragmatic RCT with Bayesian analysis. Strong design supports the null finding, though it was a secondary analysis.
When this study was published
Published in 2023. Adds to growing evidence from the OPTIMA trial about real-world opioid treatment.
The bigger picture
The evidence is accumulating that cannabis use during opioid agonist therapy is neutral with respect to treatment outcomes. This challenges the rationale for punitive policies that discharge patients from opioid treatment for cannabis use.
Questions still open
- Should cannabis-positive urine tests trigger clinical consequences in opioid treatment programs?
- Would the results differ for heavy daily cannabis users vs occasional users?
- Could specific cannabinoid profiles (high-CBD) actually improve opioid treatment outcomes?
Read the original research
Differential effect of cannabis use on opioid agonist treatment outcomes: Exploratory analyses from the OPTIMA study.
Journal of substance use and addiction treatment, 149, 209031
Citation
Elkrief, Laurent; Bastien, Gabriel; McAnulty, Christina; Bakouni, Hamzah; Hébert, François-Olivier; Socias, M Eugenia; Le Foll, Bernard; Lim, Ron; Ledjiar, Omar; Marsan, Stéphanie; Brissette, Suzanne; Jutras-Aswad, Didier. (2023). Differential effect of cannabis use on opioid agonist treatment outcomes: Exploratory analyses from the OPTIMA study.. Journal of substance use and addiction treatment, 149, 209031. https://doi.org/10.1016/j.josat.2023.209031