In a retrospective analysis of a university pain clinic, patients who received medical cannabis authorization showed a non-significant 14 mg/day decrease in opioid milligram equivalents, while long-term opioid users maintained doses 63 mg/day higher than other patients regardless of cannabis status.
Chronic pain patients, pain management clinicians, and policymakers evaluating opioid-sparing claims of medical cannabis.
Non-significant 14 mg/day opioid decrease with cannabis authorization; long-term opioid status was the dominant predictor
What the researchers found
Average opioid dose at the final time point was 33.4 mg/day OME overall. Medical cannabis authorization predicted a non-significant decrease of 14.25 mg/day OME. No significant difference between cannabis-authorized (38.51 mg/day) and non-authorized patients (32.60 mg/day). Long-term opioid users had significantly higher OME (85.34 mg/day, 63 mg/day higher than the rest, p<0.0001).
Why it matters
Claims that medical cannabis reduces opioid use are central to many advocacy and policy arguments. This real-world clinical data from a pain specialty setting shows no statistically significant opioid-sparing effect, tempering expectations while not ruling out a modest benefit.
The numbers in context
Overall average OME: 33.4 mg/day. Cannabis-authorized: 38.51 mg/day. Non-authorized: 32.60 mg/day (NS difference). Cannabis consultation: -14.25 mg/day (NS). Long-term opioid code: 85.34 mg/day (63 mg higher, p<0.0001). Overall OME trend: +0.45 mg/day per quarter (NS).
How the study worked
Longitudinal retrospective cohort analysis of electronic health records from a university-based pain clinic, July 2016 to August 2019. Longitudinal multilevel modeling with maximum likelihood estimation compared opioid milligram equivalents over time between patients with and without medical cannabis authorization.
What this study cannot tell us
Retrospective design with no randomization. Patients who sought cannabis authorization may differ from those who did not. Cannabis use was captured by authorization, not actual consumption. The 3-year study period may be too short. A university pain clinic population may not represent all chronic pain patients.
How to read the evidence
Longitudinal retrospective cohort with multilevel modeling from a single academic center, limited by observational design and authorization-as-proxy for use.
When this study was published
Published in 2026, using 2016-2019 health records.
The bigger picture
The null finding joins a growing body of clinical studies showing that population-level claims about cannabis replacing opioids are not consistently supported by individual-level data. The dominant predictor of high opioid use was having a long-term opioid use diagnosis, not cannabis access, suggesting that the opioid problem is driven by factors that cannabis alone cannot address.
Questions still open
- Would a prospective randomized trial of cannabis for opioid tapering show different results? Are there subgroups of pain patients for whom cannabis does reduce opioid needs? Does the type of cannabis product matter for opioid-sparing effects?
Common questions
Does medical cannabis reduce opioid use?
What was the strongest predictor of high opioid use?
Read the original research
Medical cannabis authorization and opioid milligram equivalents over time in patients with chronic pain: a retrospective analysis.
Pain medicine (Malden, Mass.), 27(2), 127-135
Citation
Sexton, Michelle; Glodosky, Nicholas C; Cleveland, Michael; Cuttler, Carrie; Lee, Euyhyun; Polston, Gregory R; Furnish, Timothy; Lerman, Imanuel; Schuster, Nathaniel M; Wallace, Mark S. (2026). Medical cannabis authorization and opioid milligram equivalents over time in patients with chronic pain: a retrospective analysis.. Pain medicine (Malden, Mass.), 27(2), 127-135. https://doi.org/10.1093/pm/pnaf113
Explore the wider topic
- CBD Oil Quality Guide: How to Avoid Snake Oil
- Anxiety After Quitting Weed: When to Consider Medication
- Cannabis for Chemotherapy Nausea: What the Evidence Actually Shows
- Cannabis for Chronic Pain: What the Research Actually Supports
- Cannabis and Epilepsy: The Epidiolex Story and What It Means
- Does CBD Actually Work for Anxiety? What the Evidence Shows
- Does CBD Help with Weed Withdrawal? What Studies Show
- CBD vs THC: The Differences That Actually Matter
- The Proven Medical Benefits of Cannabis: What Research Supports
- Quitting Weed Before Surgery
- Weed and Medications: What Changes When You Quit
- Quitting Weed During Pregnancy: What You Need to Know
- Quitting Weed While Pregnant: What You Need to Know
- Cannabis and Older Adults: Risks Seniors Should Know
- Cannabis and Breastfeeding: THC in Breast Milk