Comayagua

Researchers are evaluating the treatment of acute watery travelers diarrhea TD by comparing a single dose of rifaximin with loperamide to the current standard treatment of a single dose of azithromycin with loperamide. This Phase 4 randomized controlled trial aims to assess the therapeutic efficacy of these antibiotic regimens combined with loperamide. Participants are active duty military members aged 18 to 60 who have acute watery diarrhea lasting less than 96 hours that affects their daily activities or duties. Participants will be randomly assigned to one of two treatment groups one group receives a single oral dose of rifaximin 550 mg plus loperamide 4 mg initially followed by 2 mg after each unformed stool, not exceeding 16 mg per day for 2 days, and the other group receives a single oral dose of azithromycin 500 mg plus the same loperamide dosing. Both treatments are combined with loperamide as an adjunct therapy. This study uses quadruple masking to maintain objectivity. During the study, participants are asked to provide blood and stool samples at various times to assess infection and immune response. They will also complete daily symptom diaries after treatment and attend follow-up visits with study doctors to monitor illness and recovery. A brief electronic questionnaire will be completed at 3 months. Researchers will measure the primary outcome of therapeutic efficacy up to one week after treatment, along with secondary outcomes such as symptom resolution at 24 and 72 hours, recurrence of illness, and any serious adverse events within 21 days. Participants must be able to follow up for at least 7 days or have arrangements for follow-up elsewhere.