What is the recommended dosing of Vancomycin (generic name) for patients with Impaired renal function?

From the Guidelines

Vancomycin dosing should be adjusted for patients with renal impairment to prevent toxicity while maintaining therapeutic efficacy, with a recommended dose of 15-20 mg/kg (actual body weight) every 8-12 hours for patients with normal renal function. For renal impairment, the dose should be maintained but the interval extended based on creatinine clearance (CrCl) 1. The following adjustments are recommended:

• For CrCl 50-90 mL/min, dose every 12 hours
• For CrCl 10-50 mL/min, dose every 24 hours
• For CrCl <10 mL/min, dose every 48-72 hours
• For patients on hemodialysis, give 15-20 mg/kg after dialysis sessions

Therapeutic drug monitoring is essential, with target trough concentrations of 10-15 mg/L for uncomplicated infections and 15-20 mg/L for severe infections like endocarditis, osteomyelitis, or meningitis 1. Trough levels should be checked before the fourth dose in stable patients or earlier in critically ill patients. Renal function should be monitored regularly during therapy as vancomycin can cause nephrotoxicity, especially when combined with other nephrotoxic agents. Dosing should be adjusted based on trough levels and clinical response, increasing or decreasing as needed to maintain therapeutic levels while minimizing toxicity.

Some key points to consider:

• Weight-based dosing is particularly important in obese patients, who are likely to be underdosed when conventional dosing strategies are used 1
• Vancomycin loading doses may be considered for serious suspected or documented MRSA infections, but clinical data are lacking 1
• Continuous infusion vancomycin regimens are not recommended 1
• Trough vancomycin monitoring is recommended for serious infections and patients who are morbidly obese, have renal dysfunction, or have fluctuating volumes of distribution 1

From the FDA Drug Label

DOSAGE TABLE FOR VANCOMYCIN IN PATIENTS WITH IMPAIRED RENAL FUNCTION (Adapted from Moellering et al. 1) Creatinine ClearancemL/minVancomycin Dosemg/24 h 1001,545 901,390 801,235 701,080 60925 50770 40620 30465 20310 10155

The vancomycin renal dosing can be calculated using the provided table, where the dosage of vancomycin hydrochloride for injection per day in mg is about 15 times the glomerular filtration rate in mL/min.

• For patients with normal renal function, the usual daily intravenous dose is 2 g divided either as 500 mg every 6 hours or 1 g every 12 hours.
• For patients with impaired renal function, the dosage must be adjusted based on the creatinine clearance, and the initial dose should be no less than 15 mg/kg.
• The creatinine clearance can be estimated using the formula: Men: [Weight (kg) × (140 – age in years)] / 72 × serum creatinine concentration (mg/dL), Women: 0.85 × above value 2

From the Research

Vancomycin Renal Dosing

• Vancomycin dosing in patients with renal impairment is crucial to achieve optimal therapeutic levels while minimizing the risk of nephrotoxicity 3, 4, 5.
• A vancomycin dosing chart for use in patients with impaired renal function has been developed, which provides an exact dose and dosing interval based on the patient's body weight and creatinine clearance 3.
• The chart is designed to achieve an average steady-state serum concentration of approximately 15 mg/L, with predicted average steady-state serum concentrations ranging from 12.1 to 18.2 mg/L 3.
• A nomogram for vancomycin dosage adjustment in patients with various degrees of renal functional impairment has also been constructed, based on a mean steady-state serum vancomycin concentration of 15 micrograms/mL 4.
• In patients on intermittent hemodialysis, vancomycin dosing is mainly influenced by the timing of administration, the type of filter used, and the duration of dialysis, with a weight-based loading dose of 20-25 mg/kg recommended 5.
• Population pharmacokinetic modelling and simulations have been used to determine optimal loading and maintenance doses for continuous infusion of vancomycin in critically ill patients, with a 25-mg/kg loading dose and maintenance doses ranging from 1000-4500 mg/day recommended depending on renal function 6.
• The optimal maintenance dose for low renal function (CLCr < 45 mL/min) is 1000-1500 mg/day, while for augmented renal clearance (CLCr > 130 mL/min) the dose should be up to 3500 mg/day or even 4500 mg/day to achieve adequate exposure 6.