Gentamicin in neonatal infection: once versus twice daily dosage

J Med Assoc Thai. 2001 Aug;84(8):1109-15.


Fifty-four neonates were included and completed the study. Twenty-seven neonates were given 2.0-2.5 mg/kg of gentamicin twice daily while 27 neonates were given 4.0-5.0 mg/kg of gentamicin once daily. The twice daily dose and the once daily dose group had mean steady state gentamicin peak concentrations of 5.94 +/- 1.57 mg/l and 8.92 +/- 1.59 mg/l, respectively (p<0.05) while their trough concentrations were 1.44 +/- 0.49 mg/l and 0.90 +/- 0.35 mg/l, respectively (p<0.05). There were 3 neonates (11.11%) in the twice daily dose group whose peak and trough level were not within the desirable therapeutic range, two patients with too high trough level (>2 mg/l) and one with subtherapeutic peak level (<4 mg/l). Only one patient in the once daily group had undesirable trough level that was higher than 1.5 mg/l but less than 2 mg/l. Treatment with a once daily dose did not present more nephrotoxity than a twice daily dose regimen and had the tendency to have less effect on renal function. Once daily dosage can achieve the equivalent efficacy compared to a twice-daily dosage regimen. All neonates in twice daily and once daily dosage groups showed improvement in clinical outcome. Therefore, a once daily dose of gentamicin with 4.0-5.0 mg/kg could be an appropriate regimen in term neonates during the first 7 days of life. This regimen produces peak concentration that may have greater clinical efficacy and trough concentration with less toxicity than conventional dosing regimen.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Anti-Bacterial Agents / administration & dosage*
  • Anti-Bacterial Agents / adverse effects
  • Anti-Bacterial Agents / metabolism
  • Bacterial Infections / blood
  • Bacterial Infections / drug therapy*
  • Body Weight
  • Creatinine / blood
  • Drug Administration Schedule
  • Drug Monitoring
  • Female
  • Gentamicins / administration & dosage*
  • Gentamicins / adverse effects
  • Gentamicins / metabolism
  • Gestational Age
  • Humans
  • Infant, Newborn
  • Kidney Diseases / blood
  • Kidney Diseases / chemically induced
  • Male
  • Metabolic Clearance Rate
  • Prospective Studies
  • Thailand
  • Therapeutic Equivalency
  • Time Factors
  • Treatment Outcome


  • Anti-Bacterial Agents
  • Gentamicins
  • Creatinine