Antimicrobial agents in patients with renal insufficiency.

The dosage or the time interval of administration (or both) of many antimicrobial agents must be adjusted in anephric patients or those with compromised renal function. Antimicrobial agents that must be adjusted include most but not all of the penicillins, the cephalosporins, the aminoglycosides, vancomycin, and trimethoprim-sulfamethoxazole. The maximal doses of these agents should be decreased in proportion to the reduction of renal function. The dosage of chloramphenicol, clindamycin, rifampin, oxacillin, and nafcillin probably need not be adjusted if hepatic function is essentially normal. The suggested doses are relatively crude guidelines to initial antimicrobial therapy. Administration of the initial dose should be followed by serum antimicrobial assays for accurate adjustment of the dosage. The efficacy of therapy and the possible occurrence of toxicity should be carefully monitored in all patients but particularly in those with renal insufficiency.