A rigorous analysis across US states from 2006-2020 found neither recreational nor medical cannabis legalization significantly associated with opioid prescriptions or overall overdose deaths.
Policy makers and addiction researchers.
No significant association between cannabis legalization and opioid prescriptions or deaths
What the researchers found
Using a generalized difference-in-differences approach, neither type of legalization was significantly associated with opioid outcomes. Exception: recreational laws showed a possible reduction in synthetic opioid deaths (4.9 fewer per 100,000; P=.04).
Why it matters
This challenges earlier research suggesting cannabis legalization reduces opioid harm by using more rigorous methods.
The numbers in context
13 states recreational; 23 medical; 2006-2020; possible 4.9 fewer synthetic opioid deaths per 100,000 (P=.04)
How the study worked
Quasiexperimental generalized difference-in-differences using annual state-level data from 2006-2020.
What this study cannot tell us
State-level data. Borderline p-value for synthetic opioid finding. Study ended 2020.
How to read the evidence
Methodologically strong quasiexperimental design addressing known biases.
When this study was published
Published in 2024 with data from 2006-2020.
The bigger picture
Earlier findings linking legalization to opioid reductions may have been driven by statistical biases.
Questions still open
- Why might recreational laws specifically affect synthetic opioid deaths?
- Would longer follow-up show different patterns?
Common questions
Does cannabis legalization reduce opioid deaths?
Any positive finding?
Read the original research
Recreational and Medical Cannabis Legalization and Opioid Prescriptions and Mortality.
JAMA health forum, 5(1), e234897
Citation
Nguyen, Hai V; McGinty, Emma E; Mital, Shweta; Alexander, G Caleb. (2024). Recreational and Medical Cannabis Legalization and Opioid Prescriptions and Mortality.. JAMA health forum, 5(1), e234897. https://doi.org/10.1001/jamahealthforum.2023.4897