Infective gastroenteritis in young children is characterised by the sudden onset of diarrhoea, with or without vomiting. Most cases are due to an enteric virus, but some are caused by bacterial or protozoal infections. The illness usually resolves without treatment within days; however, symptoms are unpleasant and affect both the child and family or carers. Severe diarrhoea can quickly cause dehydration, which may be life threatening.

Gastroenteritis is very common, with many children having more than one episode a year. Parents and carers often manage their child's illness at home, and may not seek professional advice. However, many parents and carers do seek advice from healthcare professionals either remotely (for example, through NHS Direct), in the community, or in primary or secondary care. Approximately 10% of children younger than 5 years present to healthcare services with gastroenteritis each year (Van Damme et al. 2007). In a UK study, diarrhoeal illness accounted for 16% of medical presentations to a major paediatric emergency department (Armon et al. 2001). Although most children with gastroenteritis do not need to be admitted to hospital, many are treated as inpatients each year and often remain in hospital for several days – thereby exposing other vulnerable hospitalised children to the illness. Gastroenteritis is a significant burden on health service resources.

The management of gastroenteritis in children is multifaceted. There is evidence of variation in clinical practice, which may have a major impact on the use of healthcare resources.

This guideline applies to children younger than 5 years who present to a healthcare professional for advice in any setting. It covers diagnosis, assessment of dehydration, fluid management, nutritional management and the role of antibiotics and other therapies. It provides recommendations on the advice to be given to parents and carers, and also considers when care should be escalated – from home management through to hospital admission.

The guideline will assume that prescribers will use a drug's summary of product characteristics to inform their decisions for individual patients.