Recent data on monitoring serum levels of aminoglycosides and vancomycin.

Serum level monitoring of aminoglycosides or vancomycin is warranted in hig h-risk patients by the narrow therapeutic margin and substantial interindiv idual pharmacokinetic variation that characterize these drugs. The customiz ed dosage technique derived from population studies allows to determine the effective dosage rapidly, based on the results of a few plasma level assay s. The concentration-dependant effect of aminoglycosides warrants once-dail y administration, which provides both a concentration peak responsible for marked and sustained bactericidal activity and low residual concentrations associated with a decreased risk of toxicity. The effect of vancomycin, in contrast, is time-dependent, so that administration via a continuous intrav enous infusion increases the time spent with effective and nontoxic plasma levels. Monitoring serum levels of aminoglycosides and vancomycin is a cost -saving approach when used by health care providers with adequate training in pharmacokinetics.