A study looked at children who went to the emergency department for vomiting due to gastroenteritis. Researchers followed them for seven days after they went home. They wanted to see how often kids had more vomiting and needed to go back for care.
The study found that about 9% of children had three or more vomiting episodes after leaving the ER. Among these children, over 40% had an unscheduled doctor visit within a week. This was much higher than the 8% rate for children who stopped vomiting.
Also, children with ongoing vomiting were more likely to get IV fluids or be hospitalized. About 11% needed IV fluids, compared to less than 2% of other children. Hospitalization rates were also higher, though the difference was not as large.
The study did not test ondansetron directly in this analysis. It looked at children from a previous trial where some got the medicine at home. The results suggest that kids with persistent vomiting may benefit from home treatment, but more research is needed.
Limitations include that this was a secondary analysis, not the main study goal. Follow-up data was missing for some children. The findings show associations, not proof that ondansetron causes these outcomes.