Ondansetron to augment oral rehydration:

In a study in 215 children 6mo-10yo with gastroenteritis randomized to ondansetron PO x 1 vs. placebo, followed by a trial of oral rehydration, the ondansetron group had sig. lower incidence of need for IV hydration (14% vs. 31%) though incidence of hospitalization was not sig. diff. (NEJM 354:1698, 2006--JW)