Travellers' diarrhea.

Travellers' diarrhea is reported to affect one-third of those journeying to the tropics. The incidence varies with the destination and risks taken by travellers. Most people are affected by the third day of travel by usually short-lived symptoms. Interest in prevention and treatment reflects the size of the problem and not the severity of the syndrome. Prevention is best achieved by dietary precautions. Prophylactic drugs should be reserved for those likely to suffer most severely or who have the greatest need to avoid symptoms. Treatment should usually be limited to fluid replacement and non-antimicrobial drugs unless circumstances are exceptional.