The desired peak serum concentration of gentamicin is 5 to 12 mg/L,. The appropriate adjustment for a peak serum concentration that is higher than the desired range is to decrease the dose of the antibiotic.
Furosemide has no role in the treatment of gentamicin overdosage or toxicity. In fact, the addition of furosemide increases the potential risk of oto- and nephrotoxicity.
The desired trough
serum concentration of gentamicin is 0.5 to 1.0 mg/L, and the concentration
reported for the infant in the vignette is within that desired range. Therefore,
no adjustment in the dosing interval is warranted.
The pharmacokinetics, antimicrobial profile, and adverse effects of tobramycin are similar to those of gentamicin. Replacing one aminoglycoside with another is unlikely to be of any benefit.
Boreus LO. Therapeutic drug monitoring. In: Yaffe SJ, Aranda JV, eds.
Pediatric Pharmacology: Therapeutic Principles in Practice. 2nd ed.
Philadelphia, Pa: WB Saunders Co; 1992:63-71
de Hoog M, Schoemaker RC, Mouton JW, van den Anker JN. Tobramycin
population pharmacokinetics in neonates. Clin Pharmacol Ther.
Hayani KC, Hatzopoulos FK, Frank AL, et al. Pharmacokinetics of
once-daily dosing of gentamicin in neonates. J Pediatr. 1997;131:78-80