Gentamicin in neonates: the need for loading doses.
One hundred eighty-four neonates had gentamicin serum concentrations measured twice after an initial loading dose of 5 mg/kg infused over 1 hour. Gentamicin concentrations immediately postinfusion were calculated using a one-compartment pharmacokinetic model. The extrapolated peak gentamicin concentrations achieved with the 5 mg/kg loading dose was optimal (between 5 and 12 micrograms/ml) in 94% of cases. Had an initial dose of 2.5 mg/kg been given as suggested in most references, peak concentrations 5 mg/kg or higher would only have been achieved in 5% of neonates less than 28 weeks' gestation, 10% of neonates 28 to 30 weeks' gestation, 11% of neonates 31 to 34 weeks' gestation, and 36% of neonates more than 34 weeks' gestation. Our data support the need for greater loading doses of gentamicin in newborns. Our recommendation of 5 mg/kg achieves gentamicin concentrations known to be safe and effective.
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Greensboro Area Health Education Center, Moses H. Cone Memorial Hospital, NC 27401.
Ransom
J L
JL
Weaver
R L
RL
D004305:Dose-Response Relationship, Drug; D005839:Gentamicins / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000188:drug therapy*; D011446:Prospective Studies; D018805:Sepsis / Q000188:drug therapy
D005839:Gentamicins