The Emerging Role of Nonabsorbable Oral Antibiotic Therapy in the Management of Travelers’ Diarrhea*

The shortand long-term consequences associated with diarrhea in travelers highlight the importance of the effective management of this illness. The use of nonabsorbed, orally administered antibiotics has been proposed as an important strategy for overcoming limitations of currently available treatments for infectious diarrhea in travelers. Several nonabsorbed or poorly absorbed antibiotics have been shown to be effective for infectious diarrhea. Rifaximin, the nonabsorbed (<0.5%) antibiotic that has been most extensively studied for infectious diarrhea, demonstrates all of the advantages posited by proponents of the strategy of using nonabsorbed antimicrobial therapy for enteric infections: rifaximin achieves high luminal concentrations to eradicate causative pathogens; shows no systemic toxicity; has tolerability and safety profiles comparable to those of placebo; and has gutspecific activity that limits its use to enteric infections. In more than 15 years of clinical use for enteric infections, rifaximin has not been associated with bacterial resistance. (Adv Stud Med. 2003;3(10A):S951-S958) I nfectious diarrhea is a common problem among travelers from developed to developing countries—a group that includes tourists, business travelers, students, foreign-aid volunteers, workers of government and nongovernment organizations, and military personnel. For example, in a study of 140 western Canadian employees who traveled on international business, 45% reported infectious diarrhea as a travel-related health problem. The only more common health problem associated with travel was jet lag. Similarly, infectious diarrhea was one of the primary illnesses experienced by US, Canadian, and British troops deployed to the Arabian desert during the Gulf War in August 1990. Across studies, the incidence rate of infectious diarrhea among those traveling from developed to developing countries ranges from 20% to 90%, with the degree of risk dependent on factors such as the traveler’s country of origin, destination country, age, duration of stay, season of travel, and standard of accommodations. This incidence has recently been confirmed among more than 65 000 travelers, mainly vacationers, at 4 frequent destinations. On average, untreated travelers’ diarrhea lasts 4 days, but may extend to 1 week or more in approximately 15% of cases. Travelers’ diarrhea can necessitate bed rest and cause sufferers to alter their itineraries and cancel planned activities. These consequences are often costly for the vacationer and can be particularly disruptive for those who are required to work abroad. Apart from causing acute distress, infectious diarrhea in unusual cases can lead to complications such as arthritis, Guillain-Barré syndrome, and, rarely, death. It occasionally has been linked to the development of chronic enteric conditions, such as irritable bowel syndrome. REVIEW