From the Research
Gentamicin should be administered as a one-time dose of 7 mg/kg based on total body weight for the treatment of urinary tract infections (UTIs), as this dosing strategy has been shown to increase the probability of target attainment and minimize the risk of nephrotoxicity and ototoxicity 1. This recommendation is based on the most recent and highest quality study available, which suggests that a gentamicin starting dose of 7 mg/kg is the optimal strategy for increasing the probability of target attainment after the first administration for the most commonly used pharmacokinetic/pharmacodynamic (PK/PD) targets in adults and children older than 1 month, including critically ill patients 1. Some key points to consider when administering gentamicin for UTIs include:
- Assessing the patient's renal function before administering gentamicin, as dose adjustments may be necessary for those with impaired kidney function
- Administering the medication intravenously over 30-60 minutes or intramuscularly
- Monitoring patients for potential side effects and advising them to maintain adequate hydration during treatment
- Considering therapeutic drug monitoring (TDM) for optimization of the dosing interval, targeting a trough concentration of at least < 2 mg/L but preferably < 0.5-1 mg/L, to reduce nephrotoxicity 1. It's worth noting that the evidence from older studies, such as those published in 1978 2, 1976 3, 1999 4, and 1987 5, may not be as relevant to current clinical practice, as they may not reflect the most up-to-date dosing strategies and PK/PD targets. Therefore, the most recent study from 2022 1 should be prioritized when making treatment decisions.