Young Children at Higher Risk of Persistent Vomiting in ED May Benefit From prescription of Ondansetron at home: JAMA

A new research published in the Journal of the American Medical Association revealed that out of children presenting to the emergency department (ED) with vomiting, younger children and those ill for 24–48 hours with 10 or more vomiting episodes at presentation were more likely to continue vomiting after discharge. These findings suggest that such high-risk children may particularly benefit from being prescribed ondansetron for home use.

Acute gastroenteritis (stomach virus) is one of the leading causes of vomiting and dehydration in children worldwide. Although ondansetron has been shown to improve outcomes when prescribed for home use after ED discharge, studies suggest that only about one-third of children continue vomiting after leaving the hospital, raising questions about which patients benefit most from the medication.

Thus, this research analyzed data from 977 children aged 6 months to younger than 18 years who presented to emergency departments between September 2019 and June 2024 with vomiting caused by gastroenteritis. All participants were followed for 7 days after discharge. The primary outcome was persistent vomiting, defined as over 3 vomiting episodes within 24 hours after leaving the ED. Unplanned healthcare visits, need for intravenous fluids, and hospitalization within one week were included as secondary outcomes. 

Among the children studied, 80 of 927 participants (8.6%) experienced persistent vomiting after discharge, where the study found younger age to be the strongest predictor. Children between 6 months and under 2 years old were significantly more likely to continue vomiting after returning home.

Additional risk factors included being ill for 24 to 48 hours before arriving at the ED and experiencing 10 or more vomiting episodes in the previous 24 hours. These variables were incorporated into a predictive scoring model designed to help clinicians identify high-risk patients. According to this model, children scoring 4 points or higher had a 13.6% probability of experiencing persistent vomiting after discharge. While the model showed moderate predictive accuracy, it could still provide practical guidance in busy emergency settings.

Also, children who experienced ongoing vomiting were far more likely to require additional medical care. Over 41% returned for unscheduled healthcare visits when compared with fewer than 8% of children whose vomiting resolved. They were also more likely to require intravenous fluids and hospitalization during the following week. Overall, the findings of this study illuminate the potential value of selective prescribing rather than routine use of ondansetron for all pediatric gastroenteritis patients. 

Reference:

Sumner, M., Xie, J., Williamson-Urquhart, S., Plint, A. C., Dixon, A., Beer, D., Joubert, G., Finkelstein, Y., Pechlivanoglou, P., Klassen, T., Freedman, S. B., & Pediatric Emergency Research Canada (PERC). (2026). Persistent vomiting among children with acute gastroenteritis: A secondary analysis of a randomized clinical trial: A secondary analysis of a randomized clinical trial. JAMA Network Open, 9(5), e2610898. https://doi.org/10.1001/jamanetworkopen.2026.10898