To the Editor.
—We read with interest the article by Cooper and Bennett, on drug-induced nephrotoxicity, which appeared in the July 1987 issue of the Archives.1 The authors should be commended on the excellent and thoroughly detailed review of this complex subject, in particular, the explanation regarding aminoglycoside-induced renal dysfunction. Although dosing recommendations were a minor portion of the article, there are a few areas regarding aminoglycoside dosing that we would like to address.The authors' recommended maintenance dose of aminoglycosides (1.0 mg/kg of body weight [approximately 3.0 mg/kg/d]) may not be sufficient to produce "therapeutic" peak serum concentrations, especially in critically ill patients and patients with respiratory infections. A study by Zaske et al2 demonstrated an average maintenance dose requirement of 4.5 mg/kg/d of gentamicin to obtain peaks of 6.9 μg/mL. Peak gentamicin/ tobramycin concentrations of greater than 4.0 to 5.0 μg/mL achieved early in therapy have