General Principles

Aminoglycosides exert their bactericidal effect by binding to the bacterial ribosome, causing misreading during translation of bacterial messenger RNA into proteins. These drugs are often used in combination with cell wall–active agents (i.e., β-lactams and vancomycin) for treatment of some severe infections caused by gram-positive and gram-negative aerobes. Use in combination with cell wall–active antibiotics can lead to synergistic killing. Aminoglycosides do not have activity against anaerobes, and their activity is impaired in the low pH/low oxygen environment of abscesses. Cross-resistance among aminoglycosides is common, but not absolute, and susceptibility testing with each aminoglycoside is recommended. Use of these antibiotics is limited by significant nephrotoxicity and ototoxicity.