Furazolidone versus ampicillin in the treatment of traveler's diarrhea.

Ninety-four U.S. students who acquired diarrhea in Mexico were treated with furazolidone (47 subjects) or ampicillin (47 subjects) on a double-blind random basis. Of 47 students, 26 (55%) who received furazolidone (100 mg four times daily for 5 days) recovered from illness within 48 h after initiation of therapy, in contrast to 15 of 47 (32%) who received ampicillin (500 mg four times daily for 5 days) (P less than 0.05). Altogether, 74% of students treated with furazolidone and 49% of those receiving ampicillin were well within 72 h (P less than 0.05). When furazolidone was compared with ampicillin, clinical illness was shortened on the average from 65 to 61 h for enterotoxigenic Escherichia coli diarrhea, from 83 to 58 h for shigellosis, from 82 to 51 h for diarrhea unassociated with a detectable agent, and from 72 to 57 h for all cases irrespective of etiology. Although not dramatically effective in the current trial, the broad spectrum of activity of furazolidone is of interest. Because of in vitro activity against Campylobacter strains and known effectiveness in treating giardiasis, furazolidone should be considered in therapy for diarrhea of unknown etiology in certain settings when laboratory processing of stools for etiological agent is not feasible.