rethinkTHC Search
Menu
Study breakdown

Getting a medical cannabis license did not reduce opioid prescription use in Rhode Island

Retrospective CohortModerate evidence
The takeaway

In a population-based study linking medical cannabis registry and prescription monitoring data, obtaining a medical cannabis license was not associated with any change in opioid prescription use.

Policymakers, pain management clinicians, and researchers studying cannabis-opioid substitution.

No change in opioid prescriptions after medical cannabis licensure (OR 0.99)

What the researchers found

Among 5,296 medical cannabis license holders in Rhode Island, licensure was not associated with changes in odds of filling any opioid prescription (OR 0.99), filling prescriptions at 50+ morphine equivalent dose (OR 0.93), or at 90+ MED (OR 0.99). None of these associations were statistically significant.

Why it matters

Many states authorize medical cannabis as an alternative to opioids for pain. This study finds no evidence that obtaining a medical cannabis license actually reduces opioid prescription use.

The numbers in context

5,296 medical cannabis license holders. Any opioid prescription OR 0.99 (CI 0.94-1.05). 50+ MED OR 0.93 (CI 0.84-1.04). 90+ MED OR 0.99 (CI 0.86-1.15). All non-significant.

How the study worked

Population-based retrospective cohort linking Rhode Island medical cannabis registry with prescription drug monitoring program data (April 2016-March 2019). Within-person analysis examined changes in opioid prescriptions before and after cannabis licensure.

What this study cannot tell us

Cannot confirm whether license holders actually used cannabis. Prescription monitoring captures filled prescriptions, not consumption. Rhode Island-specific findings may not generalize.

How to read the evidence

Strong population-based design with within-person analysis, but licensure is an imperfect proxy for actual cannabis use.

When this study was published

Published in 2022 with data from 2016-2019.

The bigger picture

The null finding challenges the narrative that medical cannabis licenses naturally lead to opioid reduction and highlights the need for randomized trials to test cannabis as an opioid alternative.

Questions still open

  • Do medical cannabis patients who actually use cannabis regularly reduce opioid use? Would results differ with cannabis consumption data rather than licensure alone?

Common questions

Doesn't medical cannabis reduce opioid use?
This study found no evidence for that. Having a medical cannabis license was not associated with any change in opioid prescription patterns, including at high doses.
Why might the results be null?
Having a license doesn't mean using cannabis, and using cannabis doesn't necessarily mean substituting it for opioids. The study measured licensure, not actual cannabis consumption or pain management behavior.

Read the original research

Association of medical cannabis licensure with prescription opioid receipt: A population-based, individual-level retrospective cohort study.

The International journal on drug policy, 100, 103502

Citation

Goedel, William C; Macmadu, Alexandria; Shihipar, Abdullah; Moyo, Patience; Cerdá, Magdalena; Marshall, Brandon D L. (2022). Association of medical cannabis licensure with prescription opioid receipt: A population-based, individual-level retrospective cohort study.. The International journal on drug policy, 100, 103502. https://doi.org/10.1016/j.drugpo.2021.103502

Explore the wider topic