Vancomycin Pharmacokinetics Dosing Calculator
Clinical tool for calculating initial Vancomycin maintenance doses. Auto-calculates Creatinine Clearance (CrCl) and prioritizes renal safety.
About
Vancomycin requires precise dosing to balance efficacy against the risk of nephrotoxicity and ototoxicity. This pharmacokinetic tool estimates the initial maintenance dose by calculating Creatinine Clearance (CrCl) using the Cockcroft-Gault equation. It incorporates patient-specific parameters such as weight, age, and serum creatinine to determine the Elimination Rate Constant (ke) and Volume of Distribution (Vd). The calculator targets a trough concentration of 10-20 mcg/mL, essential for treating serious MRSA infections, and alerts clinicians to renal impairment requiring interval adjustments.
Formulas
The calculator uses the Cockcroft-Gault equation for clearance and first-order kinetics for dosing:
1. Creatinine Clearance (Male):
(140 − Age) × Weight72 × SCr2. Elimination Rate Constant (ke):
ke ≈ 0.00083 × CrCl + 0.0044Females multiply CrCl by 0.85.
Reference Data
| CrCl (mL/min) | Typical Interval (τ) | Dosing Consideration |
|---|---|---|
| > 90 | q8h or q12h | Standard renal function. Higher frequency may be needed for rapid clearance. |
| 60 - 90 | q12h | Standard maintenance interval. Monitor troughs. |
| 40 - 59 | q12h or q24h | Moderate impairment. Consider extending interval to 24 hours. |
| 20 - 39 | q24h | Significant impairment. Daily dosing usually sufficient. |
| < 20 | Pulse / Level-based | Severe failure. Dose by levels (check random levels). |
| Dialysis | Post-HD | Administer loading dose, then maintenance after dialysis sessions. |
| High BMI | Weight-based cap | Use Adjusted Body Weight if >120% IBW to prevent overdose. |
| Elderly | Conservative | Assume lower muscle mass; SCr may overestimate function. |