Efficacy of bicozamycin in preventing traveler's diarrhea.

Bicozamycin was compared with a placebo in a prospective, randomized, double-blind study of the prevention of acute diarrhea among 30 American travelers newly arrived in Guadalajara, Mexico. None of the 11 subjects given bicozamycin orally for 3 wk at a dosage of 500 mg four times a day developed diarrhea as compared with an incidence of 53% diarrhea (10 of 19 subjects) in the placebo group (p = 0.003). Bicozamycin was well tolerated. Studies of changes in predominant aerobic fecal flora among the 11 subjects treated with bicozamycin showed the appearance of only one highly resistant Citrobacter freundii at the end of 1 wk of therapy and only a total of six resistant isolates at the end of 3 wk. All resistant isolates failed to transfer this resistance to a recipient Escherichia coli. Bicozamycin seems to be well suited and safe as a prophylactic agent against traveler's diarrhea.