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 initial dose should be no less than 15 mg/kg, even in patients with mild to moderate renal insufficiency. The table is not valid for functionally anephric patients For such patients, an initial dose of 15 mg/kg of body weight should be given to achieve prompt therapeutic serum concentrations. The dose required to maintain stable concentrations is 1. 9 mg/kg/24 hr. In patients with marked renal impairment, it may be more convenient to give maintenance doses of 250 to 1,000 mg once every several days rather than administering the drug on a daily basis. In anuria, a dose of 1,000 mg every 7 to 10 days has been recommended
The renal dose adjustment for Vancomycin in patients with impaired renal function can be calculated using the provided dosage table, which is based on creatinine clearance.
- The dosage of vancomycin hydrochloride for injection per day in mg is about 15 times the glomerular filtration rate in mL/min.
- For functionally anephric patients, an initial dose of 15 mg/kg of body weight should be given, followed by a maintenance dose of 1.9 mg/kg/24 hr.
- In patients with marked renal impairment, maintenance doses of 250 to 1,000 mg once every several days may be given instead of daily doses.
- In anuria, a dose of 1,000 mg every 7 to 10 days is recommended 1.
From the Research
Vancomycin dosing should be adjusted based on the patient's renal function to minimize the risk of nephrotoxicity and ensure therapeutic efficacy, as evidenced by a study published in 2021 2. For patients with impaired kidney function:
- Calculate creatinine clearance (CrCl) using the Cockcroft-Gault equation.
- Adjust dosing as follows:
- CrCl > 90 mL/min: Standard dosing (15-20 mg/kg every 8-12 hours)
- CrCl 60-90 mL/min: 15-20 mg/kg every 12-24 hours
- CrCl 30-59 mL/min: 15-20 mg/kg every 24-48 hours
- CrCl 15-29 mL/min: 15-20 mg/kg every 48-72 hours
- CrCl < 15 mL/min: 15-20 mg/kg every 72-96 hours
- Monitor trough levels before the fourth dose and adjust as needed to maintain 10-20 μg/mL for most infections.
- For patients on hemodialysis, give a loading dose of 20-25 mg/kg, then 500-750 mg after each dialysis session. A study published in 2019 3 found that loading doses of vancomycin do not increase nephrotoxicity compared to lower doses in patients with severe renal dysfunction, suggesting that higher doses may be necessary to achieve therapeutic levels in these patients. However, it is essential to prioritize the most recent and highest-quality study, which is the 2021 study 2, to guide vancomycin dosing adjustments in patients with impaired renal function. The adjustment of vancomycin dosing is crucial because vancomycin is primarily eliminated by the kidneys, and reduced renal function can lead to drug accumulation, potentially causing toxicity, as highlighted in a study published in 1997 4. Monitoring trough levels ensures therapeutic efficacy while minimizing the risk of adverse effects, particularly nephrotoxicity and ototoxicity, as emphasized in a study published in 1988 5 and another in 1983 6.