Picture 1 shows a paediatric ward in the Caribbean some years ago, when all children with diarrhoea were given intravenous fluids. Happily, with recognition of the advantages of oral rehydration therapy, this is now a rare sight. Prolonged intravenous therapy carries certain risks and is therefore to be discouraged. Firstly, if carried out in unsterile conditions, it may give rise to local or systemic infections. Secondly, overhydration may occur and cause heart failure, as in the baby in picture 2, who had to be given oxygen. Note the periorbital oedema - the opposite of sunken eyes - which indicates overhydration.