Aminoglycosides, imipenem, and aztreonam.

The aminoglycosides continue to be the cornerstone of antibiotic therapy for serious infections caused by gram-negative aerobic pathogens, even with the recent introduction of potent beta-lactams and the fluoroquinolones. Two of these newer agents are imipenem and aztreonam. Imipenem is the most expensive commercially available antibiotic, but it has the broadest range of activity, including most gram-negative and gram-positive, aerobic and anaerobic bacteria. Aztreonam, the first monobactam antibiotic to be released, has excellent activity against aerobic, gram-negative bacteria. It is not, however, simply a nonnephrotoxic replacement for aminoglycoside therapy. This article reviews the basic pharmacology and clinical utility of the aminoglycosides, imipenem, and aztreonam.