After an emergency department visit for cannabinoid hyperemesis syndrome, most patients temporarily reduced cannabis use but returned to pre-visit patterns within days, and 25% made repeat ER visits within three months.
Emergency physicians managing CHS; addiction specialists working with cannabis use disorder.
25% of CHS patients had repeat ER visits within 3 months
What the researchers found
Participants had persistent CHS symptoms (abdominal pain, nausea, cyclic vomiting) for a median of 7 days after their ED visit. Cannabis use frequency and quantity were reduced immediately after the visit but most returned to pre-visit use patterns within days. 25% of those who completed follow-up had recurrent ED visits within 3 months.
Why it matters
CHS is increasingly common as cannabis use rises, yet almost nothing is known about what happens after patients leave the ER. This study reveals a cycle of temporary reduction followed by rapid return to use, with ongoing symptoms managed at home, suggesting current ED-based interventions are insufficient to change behavior.
The numbers in context
39 patients enrolled. Median symptom persistence: 7 days post-ED visit. 25% had recurrent ED visits within 3 months. Most returned to pre-visit cannabis use patterns within days of the ED visit.
How the study worked
Prospective observational cohort of 39 patients with suspected CHS recruited from the ED during symptomatic episodes and followed for 3 months. Cannabis use practices, symptom progression, and healthcare utilization were monitored.
What this study cannot tell us
Small sample size (n=39) limits generalizability. CHS diagnosis was based on clinical suspicion without universally agreed-upon diagnostic criteria. Three-month follow-up may be too short to capture longer-term outcomes.
How to read the evidence
Preliminary: prospective design with longitudinal follow-up addresses a major knowledge gap, but the small sample (n=39) limits statistical power and generalizability.
When this study was published
2024 study.
The bigger picture
CHS is a growing challenge in emergency medicine and represents a unique form of cannabis-related harm that directly contradicts the perception of cannabis as universally low-risk. The rapid return to use despite symptoms suggests that CHS patients may need sustained outpatient support, not just acute ED care.
Questions still open
- What interventions at the ED visit would most effectively support sustained cannabis reduction? Does CHS severity worsen with repeated cycles of use and ED visits over longer timeframes?
Common questions
What is cannabinoid hyperemesis syndrome?
Why do patients resume cannabis use despite symptoms?
Read the original research
Cannabinoid hyperemesis syndrome: Clinical trajectories and patterns of use three months following a visit to the emergency department.
Academic emergency medicine : official journal of the Society for Academic Emergency Medicine, 31(5), 463-470
Citation
Wightman, Rachel S; Metrik, Jane; Lin, Timmy R; Collins, Alexandra B; Beaudoin, Francesca L. (2024). Cannabinoid hyperemesis syndrome: Clinical trajectories and patterns of use three months following a visit to the emergency department.. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine, 31(5), 463-470. https://doi.org/10.1111/acem.14773