Amoxicillin/clavulanate therapy of respiratory tract infections: a microbiologic perspective.

The development of beta-lactamase-producing strains of the common respiratory tract pathogens Hemophilus influenzae and Moraxella catarrhalis has caused increasing resistance to a number of antimicrobial agents, including ampicillin and amoxicillin, that are traditionally used to treat respiratory tract infections. Because antimicrobial therapy for upper and lower respiratory tract infections is usually empiric, an understanding of beta-lactamase-mediated resistance and its implications for antibiotic therapy is critical for the successful treatment of these infections.