Gastroenteritis describes a group of diseases affecting the stomach or part of the intestine. 

Symptoms are often diarrhoea, sickness and stomach ache. 

As the lining of the stomach is likely to be inflamed, medicines are often immediately vomited up. 

Small frequents amounts of water; orange juice or thin soup should be taken to counter the effects of dehydration. 

Consult your Doctor if symptoms persist for more than a day or, in the case of babies, 6 hours.