In vivo inactivation of tobramycin by piperacillin

In vivo inactivation of aminoglycosides by antipseudomonal penicillins in patients with renal failure can be a significant problem when these drugs are used together in certain gram-negative infections. Our article illustrates the possible magnitude of this interaction and the resultant effect on aminoglycoside pharmacokinetic parameters. Penicillin concentrations remain relatively unaffected by this interaction. This article stresses the need for close monitoring of aminoglycoside concentrations when combined with antipseudomonal penicillins in this patient population.