Vancomycin: Initial Emperic Therapy Recommendation

Vancomycin AUC:MIC Dosing Calculator

Demographic Data

Gender:

Age (yrs):

Height (cm):

Weight (kg):

SCr (mg/dL):

AKI?

On Dialysis?

Updated empiric vancomycin equations (05/2022):

Vd (L) = 0.29 (age) + 0.33 (TBW in kg) + 11
CLv (L/hr) = [0.705 (CrCl) + 4] × 0.06
Ke = CLv / Vd

CrCl calculation:

CrCl = [(140 − Age) × Weight (kg)] / (72 × Serum Creatinine (mg/dL)) × 0.85 (if female)

Reasoning for CrCl Selection
– If ABW > 120% of IBW → Use AdjBW
– If ABW < IBW → Use TBW
– If ABW ≈ IBW → Use IBW

Special Considerations:
Some facilities may have their own guidelines (e.g., elderly > 65, if SCr < 0.8 adjust to 0.8).

AUC:MIC Dosing Calculator

CrCl (mL/min):

Maintenace Dose (mg):

Frequency (hrs):

Weight selection:

Loading dose: mg ( mg/kg)

Maintenance dose: mg ( mg/kg)

Regimen Recommendations

Dose	Freq	AUC₁	AUC₂

Recommended Range

Range (mg/day):

Est. Concentrations

Peak (mg/L): Trough (mg/L): AUC₂₄: Double AUC:

Assumes 1 g/hr infusion

Kinetic Data

Ke (hr⁻¹):

t½ (hrs):

Vd (L):

Clv (L/hr):

Dose Estimates

AUC₂₄–400:

AUC₂₄–500:

AUC₂₄–600:

Round to nearest 250 mg

Table 1. Dosing Weight Selection

Body Mass Index (BMI)	Weight to Use
BMI < 30 kg/m²	Actual Body Weight
BMI ≥ 30 kg/m²	Adjusted Body Weight

Table 2. Initial Loading and Maintenance Dose Selection

Loading Dose*	Maintenance Dose†	Initial Dosing Interval Based on Estimated CrCl and Age**
Loading Dose*	Maintenance Dose†	≥ 90 mL/min	60–89 mL/min	25–59 mL/min	< 25 mL/min
Consider in critically ill and/or severe Methicillin‑resistant Staphylococcus aureus infections: 25 mg/kg All others: 20 mg/kg	15 mg/kg/dose Q8H Max: 20 mg/kg/dose (rounded to nearest 250 mg)	Q8H Age > 40 yo, BMI ≥ 30, quadriplegic, or treatment of osteomyelitis or cellulitis: Q12H preferred	Q12H Age ≥ 65 and non‑critically ill: Q24H preferred	Q24H	Initial dosing based on Therapeutic Drug Monitoring (Pulse Dosing)^

* Loading Dose † Maintenance Dose ** Estimated CrCl and Age
^ Pulse Dosing

How to Use

Input all the data required
Click Calculate to generate parameters and kinetic model
Generate recommended dose/frequency is based on AUC 400–600 mg·hr/L

Formulas Used

Vd = (0.29 × Age) + (0.33 × Actual Body Weight) + 11
Clearance Vanc (L/hr) = [0.705 (CrCl) + 4] * 0.06
Ke = CLv / Vd
Half-life = 0.693 / ke

References

Murphy, J.E. Clinical Pharmacokinetics, 7th Edition & Workbook.
https://www.amazon.com/Clinical-Pharmacokinetics-Workbook/dp/1585287008

IDSA 2020 Guidelines – AUC-based dosing.
https://pubmed.ncbi.nlm.nih.gov/32227354/

Fewel N. – Accuracy of vancomycin AUC values estimated with trough-only data in a veteran population
https://pubmed.ncbi.nlm.nih.gov/36477193/

Disclaimer:
This tool is provided by GuideRPH for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. All calculations should be independently verified, and clinical decisions should be based on professional judgment, official guidelines, and the individual patient’s needs. GuideRPH assumes no responsibility or liability for any errors, inaccuracies, or outcomes resulting from the use of this tool. By using this tool, you acknowledge and agree that it is to be used as a reference only and that you are solely responsible for any clinical decisions you make. This tool may not reflect the latest medical research or standards, and the user is responsible for consulting up-to-date sources.