Traveler's diarrhea: update 1983.

Each year, more than one million American travelers develop diarrhea, usually due to toxin-producing Escherichia coli. Traveler's diarrhea can be prevented with bismuth subsalicylate or doxycycline, but neither is suitable for pediatric patients. Trimethoprim-sulfamethoxazole is effective for prophylaxis and treatment in adults. It is also safe for children and may prove to be efficacious. It may be possible to avoid widespread prophylaxis and to give medication only if diarrhea develops.