Emergency department visits for a severe vomiting condition tied to long-term cannabis use have climbed sharply in the United States, a large retrospective analysis reports. Published in JAMA Network Open, the study examined more than 188 million ED records—roughly 85% of U.S. emergency visits—and found a fivefold increase in visits meeting a proxy definition for cannabinoid hyperemesis syndrome (CHS) between 2016 and 2022, with a peak during the COVID-19 pandemic.
Because CHS did not have its own ICD diagnosis code at the time (an official code was assigned in 2025), investigators led by James A. Swartz, PhD, identified probable CHS cases by the co-occurrence of cannabis use disorder and cyclical vomiting. Using that approach, the rate rose from 4.4 per 100,000 ED visits in 2016 to 22.3 per 100,000 in 2022, and reached 33.1 per 100,000 in 2020. Young adults aged 18–25 were affected disproportionately, with about a 3.5-fold higher likelihood of receiving a CHS diagnosis than older adults. At the same time, overall visits for cyclical vomiting declined, suggesting the increase was specific to cannabis-associated presentations rather than a general rise in vomiting disorders.
Clinical features
CHS often follows a prodromal phase lasting months to years, marked by worsening nausea, abdominal discomfort, and anxiety about vomiting without actual emesis. That can progress to a hyperemetic phase of recurrent, sometimes prolonged vomiting episodes, severe abdominal pain, weight loss, and a characteristic compulsion for hot showers or baths that many patients find temporarily relieving. The syndrome is sometimes colloquially called scromiting, a blend of screaming and vomiting.
Risk factors and possible drivers
Risk appears to rise with chronic, particularly daily, cannabis use. Investigators and commentators point to broader legalization, greater availability and variety of products, and higher-potency cannabis formulations as likely contributors, although the exact biological mechanisms remain uncertain. CHS was first described in Australia in 2004 and has likely been underrecognized or misdiagnosed; improved clinical awareness may account for part of the observed increase in identified cases.
Prevention and management recommendations
– Stopping cannabis use is the primary and most reliable way to prevent recurrence; sustained abstinence is the clearest treatment approach. The benefit of reducing or intermittent use for prevention is unknown.
– Clinicians advising people who use cannabis recommend avoiding very high-potency products such as wax, dabs, and shatter and paying attention to total daily THC exposure. Some experts suggest most smokers do not need products exceeding about 25% THC and should limit overall THC intake.
– If prodromal warning signs—worsening nausea or abdominal discomfort—appear, taking a break from cannabis or cutting back to see if symptoms improve is reasonable.
Study limitations and next steps
The analysis relied on a proxy definition for CHS because of the absence of a specific ICD code during the study period, so the findings cannot fully distinguish a true rise in incidence from improved recognition and coding. The authors and other experts consider both explanations plausible and call for prospective, detailed studies to clarify biological mechanisms, identify risk thresholds, and develop effective prevention and treatment strategies.
