Pharmacokinetics of a Once Daily Dosing Regimen of Gentamicin in a Patient with Delayed Wound Healing

Mohammed Qahl3, Saeed F Algahtani1, Fahad M AlQahtani2,

Pharmacokinetics of a Once Daily Dosing Regimen of Gentamicin in a Patient with Delayed Wound Healing

Document Type : Original Article

Author

Saeed F Algahtani1, Fahad M AlQahtani2, Mohammed Qahl3

1. Department of Clinical Pharmacy, Al Kharj Military Industries Corporation Hospital, 2. Drug Information and Poisoning Center, Al Kharj Military Industries Corporation Hospital,3. Department of Pharmacy, Northern Area Armed Forces Hospital

Abstract

Background: Gentamicin is used for the treatment of serious gram-negative infections and has low therapeutic index. This may lead to several side effects, though therapeutic drug monitoring (TDM) is important in gentamicin therapy.
Aim: To report the pharmacokinetics of gentamicin using a once-daily dosing regimen.
Clinical presentation and intervention: The patient was a 78-year-old male. His weight was 78 kg and he was 1.75 m in height. He was admitted to the hospital complaining of an infected wound secondary to chronic limb ischaemia. Once-daily dosing of gentamicin (360 mg by infusion over 30 minutes) was prescribed to this patient, in combination with flucloxacillin. A gentamicin blood sample was taken every day for four days (day 1 = 1.4 mg/L, day 2 = 2.1 mg/L, day 3 = 2.1 mg/L, day 4 = 1.6 mg/L). The patient’s serum creatinine was 88 μmol/L during the four days. The Hartford nomogram was used to estimate the dosage and interval for administration of gentamicin.
Conclusion: The Hartford nomogram is a valid tool to monitor the once-daily dosing regimen of gentamicin.

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