Emergency department visits for cannabinoid hyperemesis syndrome in Nevada roughly doubled after recreational cannabis commercialization in 2017, rising from about 1.1 to 2.2 per 100,000 population.
Emergency physicians, public health officials, and cannabis legalization researchers
CHS ER visits doubled after recreational cannabis commercialization
What the researchers found
Emergency department visits for CHS increased continuously from 2013 to 2021. The rate was 1.07 per 100,000 before recreational cannabis commercialization and jumped to 2.22 per 100,000 after commercialization in the third quarter of 2017, an increase of approximately 1.1 per 100,000. CHS patients were younger and included fewer males compared to other ED visitors.
Why it matters
This provides direct evidence linking recreational cannabis commercialization to a measurable increase in a specific health outcome. CHS is entirely attributable to cannabis use, making it a clean indicator of the health burden associated with expanded access.
The numbers in context
Pre-commercialization rate: 1.07 per 100,000. Post-commercialization rate: 2.22 per 100,000. Increase: approximately 1.1 per 100,000. Study period: 2013-2021. CHS patients were younger and had fewer males than non-CHS ED patients.
How the study worked
Interrupted time series analysis using Nevada State Emergency Department Databases (2013-2021). CHS patients were compared to all other ED visitors. The impact of recreational cannabis commercialization (Q3 2017) was estimated as the intervention point.
What this study cannot tell us
ICD-code-based identification may undercount CHS cases, especially before the condition became well-recognized. The time series cannot prove commercialization caused the increase, as awareness and diagnosis of CHS also improved during this period. Limited to Nevada.
How to read the evidence
Strong interrupted time series design using population-level data, though coding accuracy and diagnostic awareness changes are potential confounders.
When this study was published
2024 study using 2013-2021 data
The bigger picture
CHS ER visits serve as a canary in the coal mine for cannabis-related health system burden. The doubling in Nevada adds to similar findings in Colorado, Washington, and other legalized states, suggesting this is a consistent consequence of commercialization.
Questions still open
- How much of the increase reflects true incidence vs improved recognition? What is the CHS rate in states with longer legalization histories? Are certain cannabis products (concentrates, edibles) more likely to cause CHS?
Common questions
Did recreational cannabis legalization increase ER visits for CHS?
How common are CHS emergency visits?
Read the original research
Trends of emergency department visits for cannabinoid hyperemesis syndrome in Nevada: An interrupted time series analysis.
PloS one, 19(5), e0303205
Citation
Soh, Jaeseung; Kim, Yonsu; Shen, Jay; Kang, Mingon; Chaudhry, Stefan; Chung, Tae Ha; Kim, Seo Hyun; Hwang, Yena; Lim, Daniel; Khattak, Adam; Frimer, Leora; Yoo, Ji Won. (2024). Trends of emergency department visits for cannabinoid hyperemesis syndrome in Nevada: An interrupted time series analysis.. PloS one, 19(5), e0303205. https://doi.org/10.1371/journal.pone.0303205