Antibiotic Therapy for Acute Watery Diarrhea and Dysentery

Diarrheal disease affects a large proportion of military personnel deployed to developing countries, resulting in decreased job performance and operational readiness. Travelers' diarrhea is self-limiting and generally resolves within 5 days; however, antibiotic treatment significantly reduces symptom severity and duration of illness. Presently, azithromycin is the preferred first-line antibiotic for the treatment of acute watery diarrhea (single dose 500 mg), as well as for febrile diarrhea and dysentery (single dose 1,000 mg). Levofloxacin and ciprofloxacin are also options for acute watery diarrhea (single dose 500 mg and 750 mg, respectively) and febrile diarrhea/dysentery in areas with high rates of Shigella (500 mg once for 3 days [once daily with levofloxacin and twice daily with ciprofloxacin]), but are becoming less effective because of increasing fluoroquinolone resistance, particularly among Campylobacter spp. Another alternate for acute watery diarrhea is rifaximin (200 mg 3 times per day for 3 days); however, it should not be used with invasive illness. Use of loperamide in combination with antibiotic treatment is also beneficial as it has been shown to further reduce gastrointestinal symptoms and duration of illness. Because of regional differences in the predominance of pathogens and resistance levels, choice of antibiotic should take travel destination into consideration.