The effects of antibiotic use on gastrointestinal function.

The bacterial flora of the gastrointestinal (GI) tract plays an important role in maintaining the integrity of the enterocyte, modulating metabolic and immunologic processes, and protecting against colonization by invasive pathogens. Disruption of this finely tuned and stable gut flora by antibiotics, infection, chemotherapy, or radiation has profound effects on the protective barrier and results in overgrowth by pathogens, invasion and translocation of toxins, and life-threatening infections. Use of antibiotics promotes the emergence of resistant organisms, and multiple-antibiotic resistance has become a major public health issue. Preservation of protective species or recolonization with nonpathogenic yeasts or lactobacilli during periods of stress (infections, drugs) has begun to show promise in the management of patients receiving multiple antibiotics, particularly in hospital-acquired infections.