Effect of ondansetron on vomiting associated with acute gastroenteritis in a developing country: a meta-analysis

In high-income countries. ondansetron is an effective antiemetic in children with gastroenteritis, but data from low- and middle-income countries are sparse. This study aimed to evaluate evidences of the effectiveness of ondansetron in preventing vomiting and reducing the use of intravenous fluids in children with gastroenteritis in developing countries. A total of nine randomized controlled trials (RCTs) involving 2313 participants met the inclusion criteria. Compared with placebo, ondansetron reduced the use of intravenous rehydration (three RCTs, n = 1126, relative risk (RR) 0.60, 95% confidence interval (CI) 0.38-0.95, no significant heterogeneity, I² = 43%), the risk of failure of oral rehydration therapy among children with gastroenteritis-associated vomiting and dehydration (four RCTs, n = 1370, RR 0.58, 95% CI 0.43-0.79; no significant heterogeneity was found, I² = 39%) and risk of hospitalization (2 RCTs, n = 264, RR 0.25, 95% CI 0.09-0.73, no heterogeneity, I² = 0).Conclusions: Compared with placebo, ondansetron reduced the use of intravenous fluids in children with gastroenteritis and dehydration. It has no effect on children with gastroenteritis who do not present with dehydration in developing countries. While ondansetron is effective in controlling vomiting and reducing the rate of hospitalization, there is no evidence that it is effective in reducing the rate of readmission. What is Known: • In high-income countries, ondansetron can reduce the use of intravenous fluids in children with gastroenteritis and dehydration. • No systematic review and meta-analysis of randomized controlled trials were done in a developing country setting. What is New: • In developing countries, ondansetron reduces the use of intravenous fluids in children with gastroenteritis and dehydration. • It has no effect on children with gastroenteritis but without dehydration.