ER Visits for Cannabis Intoxication Jumped After Michigan Legalized Recreational Use

Emergency department visits for acute cannabis intoxication increased 47-70% after recreational cannabis legalization in Michigan.

Nguyen, An et al.·The American journal of emergency medicine·2024·Moderate EvidenceRetrospective Cohort
RTHC-05590Retrospective CohortModerate Evidence2024RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Retrospective Cohort
Evidence
Moderate Evidence
Sample
N=2,066

What This Study Found

After Michigan legalized recreational cannabis in December 2018, cannabis-related ED visits increased significantly (unadjusted RR 1.70; age-adjusted RR 1.47). The increase was immediate.

Key Numbers

2,177 ED visits from 2,066 patients; 671 pre-legalization, 1,506 post; unadjusted RR 1.70; age-adjusted RR 1.47; 8 hospitals

How They Did This

Retrospective observational cohort across 8 hospitals in southeast Michigan, 2016-2022, using ICD-10 codes and negative-binomial regression.

Why This Research Matters

The immediate 47% jump provides concrete evidence for health systems planning around legalization.

The Bigger Picture

This adds to evidence that recreational legalization is associated with increased ED presentations.

What This Study Doesn't Tell Us

Single health system. Relied on ICD-10 codes. Pre-existing upward trend complicates attribution.

Questions This Raises

  • ?What product types drive ED visits?
  • ?Do these visits result in significant interventions?

Trust & Context

Key Stat:
47% increase in cannabis-related ER visits after legalization (age-adjusted)
Evidence Grade:
Multi-hospital retrospective study with appropriate modeling but limited to one health system.
Study Age:
Published in 2024 with data from 2016-2022.
Original Title:
The impact of recreational cannabis legalization on ED visit rates for acute cannabis intoxication.
Published In:
The American journal of emergency medicine, 84, 124-129 (2024)
Database ID:
RTHC-05590

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Looks back at existing records to find patterns.

What do these levels mean? →

Frequently Asked Questions

Did the increase happen right away?

Yes, in the first month after legalization.

Which age groups were most affected?

All age groups, with middle-aged adults particularly notable.

Read More on RethinkTHC

Cite This Study

RTHC-05590·https://rethinkthc.com/research/RTHC-05590

APA

Nguyen, An; Lee, Ray; Zhao, Lili; Qu, Lihua; Todd, Brett. (2024). The impact of recreational cannabis legalization on ED visit rates for acute cannabis intoxication.. The American journal of emergency medicine, 84, 124-129. https://doi.org/10.1016/j.ajem.2024.07.041

MLA

Nguyen, An, et al. "The impact of recreational cannabis legalization on ED visit rates for acute cannabis intoxication.." The American journal of emergency medicine, 2024. https://doi.org/10.1016/j.ajem.2024.07.041

RethinkTHC

RethinkTHC Research Database. "The impact of recreational cannabis legalization on ED visit..." RTHC-05590. Retrieved from https://rethinkthc.com/research/nguyen-2024-the-impact-of-recreational

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.