What is the recommended dose of vancomycin for the treatment of pneumonia?

Vancomycin Dosing for Pneumonia

For the treatment of pneumonia, vancomycin should be dosed at 15-20 mg/kg/dose IV every 8-12 hours for adults, with target trough concentrations of 15-20 μg/mL. 1

Standard Dosing Recommendations

• Adults with normal renal function: 15-20 mg/kg every 8-12 hours
• Children with serious infections: 15 mg/kg/dose every 6 hours
• Seriously ill patients: Consider loading dose (25-30 mg/kg) to rapidly achieve therapeutic levels
• Target trough concentrations: 15-20 μg/mL for pneumonia

Dosing Considerations Based on Renal Function

Renal function significantly impacts vancomycin dosing:

• Normal renal function (CrCl >80 mL/min): 15-20 mg/kg every 8-12 hours
• Moderate renal impairment (CrCl 50-60 mL/min): 25 mg/kg every 24 hours
• Severe renal impairment (CrCl 30 mL/min): 18 mg/kg every 48 hours 1

Monitoring Recommendations

• Obtain serum trough concentrations at steady state (before 4th or 5th dose)
• Target trough of 15-20 μg/mL correlates with an AUC/MIC ratio >400, which is the pharmacodynamic parameter that best predicts vancomycin efficacy 1
• Monitor renal function regularly, especially with:
  • Trough levels ≥15 mg/L (5.2 times higher risk of nephrotoxicity) 2
  • Concomitant aminoglycoside use (2.67 times higher risk) 2
  • Extended duration of therapy (12% increased risk per additional day) 2

Important Clinical Considerations

• Standard dosing of 1g IV every 12 hours is unlikely to achieve target trough concentrations of 15-20 μg/mL in critically ill patients with pneumonia 3
• At least 1g IV every 8 hours is needed for many patients with normal renal function to achieve appropriate trough levels 3
• Infuse vancomycin over at least 1 hour to reduce the risk of "red man syndrome" 1
• For patients with MRSA pneumonia, higher doses are often required to achieve therapeutic levels, particularly in critically ill patients 4

Pitfalls and Caveats

• More than 70% of critically ill patients fail to reach the recommended therapeutic trough concentrations with standard dosing 4
• Nephrotoxicity risk increases significantly with higher trough levels (7% at <10 mg/L vs. 34% at >20 mg/L) 2
• Using actual body weight for initial dosage calculation in obese patients, with careful monitoring of serum levels 1
• The time to nephrotoxicity decreases with higher trough levels (8.8 days at <15 mg/L vs. 7.4 days at >20 mg/L) 2

Weight-based dosing (15-20 mg/kg) rather than fixed dosing (e.g., 1g every 12 hours) is essential to achieve target trough concentrations, especially in critically ill patients with pneumonia.