Vomiting in children with acute gastroenteritis is a major factor of failure of oral rehydration therapy. Effective symptomatic treatment of vomiting would lead to an important reduction in the use of Intravenous Fluid Therapy. Available evidence on symptomatic treatment of vomiting shows the efficacy of the most recently registered molecule (ondansetron) but a proper evaluation of antiemetics drugs largely used in clinical practice, such as domperidone, is lacking.

The aim of this multicentre, double-blind randomized controlled trial is to compare the efficacy of ondansetron and domperidone for the symptomatic treatment of vomiting in children with acute gastroenteritis who have failed Oral Rehydration Therapy.

Vomiting in children with acute gastroenteritis (AG) is not only a direct cause of fluid loss but it is also a major factor of failure of oral rehydration therapy (ORT). Physicians who provide care to paediatric patients in the emergency department (ED) usually prescribe intravenous fluid therapy (IVT) for mild or moderate dehydration when vomiting is the major symptom. Thus, effective symptomatic treatment of vomiting would lead to an important reduction in the use of IVT and, consequently, of the duration of hospital stay and of frequency of hospital admission. Available evidence on symptomatic treatment of vomiting shows the efficacy of the most recently registered molecule (ondansetron) but a proper evaluation of antiemetics drugs largely used in clinical practice, such as domperidone, is lacking.

The aim of this multicentre, double-blind randomized controlled trial conducted in paediatric Emergency Departments is to compare the efficacy of ondansetron and domperidone for the symptomatic treatment of vomiting in children with AG who have failed Oral Rehydration Therapy.

The trial results would provide evidence on the efficacy of domperidone, which is largely used in clinical practice despite the lack of proper evaluation and a controversial safety profile, as compared to ondansetron, which is not yet authorized in Italy despite evidence supporting its efficacy in treating vomiting. The trial results would contribute to a reduction in the use of IVT and, consequently, in hospital admissions in children with AG. The design of this RCT, which closely reflect current clinical practice in EDs, will allow immediate transferability of results

Inclusion Criteria:

1. age from 1 to 6 years;
2. presumptive clinical diagnosis of acute gastroenteritis in patients with vomiting, with or without diarrhoea;
3. more than three episodes of non-bilious, non-bloody vomiting within the previous 24 hours;

Exclusion Criteria:

1. treatment with antiemetics or antidiarrhoic drugs in the 6 hours prior to access to ED;
2. underlying chronic diseases (eg, malignancy, gastroesophageal reflux, migraine, renal failure, hypoalbuminemia, liver disease);
3. severe dehydration: weight loss>10% or standardized clinical dehydration score >=18 for children aged 12-24 months and >=16 for older children;
4. known hypersensitivity to ondansetron or domperidone;
5. previous enrolment in the study.