What is the recommended dose of vancomycin for adults?

Vancomycin Dosing Recommendations for Adults

For adults with normal renal function, the recommended vancomycin dosage is 15-20 mg/kg every 8-12 hours, not to exceed 2 g per dose. 1, 2

Standard Dosing Guidelines

• Normal renal function:

  • 15-20 mg/kg every 8-12 hours (typically 2 g daily divided as 500 mg every 6 hours or 1 g every 12 hours) 2
  • For serious infections (bacteremia, endocarditis, osteomyelitis, meningitis, pneumonia): Target trough concentrations of 15-20 μg/mL 1
  • For less severe infections: Lower trough concentrations may be appropriate

• Loading dose:

  • For seriously ill patients (sepsis, meningitis, pneumonia, endocarditis): Consider 25-30 mg/kg loading dose to rapidly achieve therapeutic levels 1

• Administration rate:

  • Maximum 10 mg/min or over at least 60 minutes (whichever is longer) 2
  • Slower infusion (1.5-2 hours) for doses exceeding 1g to prevent "red man syndrome" 1

Dosage Adjustments

• Renal impairment:

  • Daily dose (mg) ≈ 15 times the glomerular filtration rate in mL/min 2
  • Initial dose should not be less than 15 mg/kg even in mild-moderate renal impairment 2
  • For functionally anephric patients: 15 mg/kg initial dose, then adjust based on levels 2

• Obese patients:

  • Use actual body weight for initial dosage calculation 1
  • Monitor serum levels closely

Therapeutic Monitoring

• Obtain trough levels at steady state (before 4th or 5th dose) 1
• Target trough concentrations:
  • 15-20 μg/mL for serious infections 1
  • Lower concentrations may be appropriate for less severe infections
• For isolates with vancomycin MIC >2 μg/mL (VISA or VRSA), consider alternative agents 3

Special Considerations

• For persistent MRSA bacteremia or treatment failures:

  • Consider high-dose daptomycin (10 mg/kg/day) in combination with another agent 3
  • Ensure removal of infection foci and perform surgical debridement when indicated 3

• Risk factors for toxicity:

  • Higher serum levels (>25 mg/L)
  • Underlying renal impairment
  • Concomitant nephrotoxic medications 1

Common Pitfalls to Avoid

1. Underdosing: Standard 1g every 12 hours often fails to achieve target trough concentrations of 15-20 mg/L in critically ill patients 4

2. Excessive infusion rates: Infusing faster than 10 mg/min increases risk of "red man syndrome" 2

3. Inadequate monitoring: Failure to check trough levels before the 4th or 5th dose may lead to suboptimal therapy or toxicity 1

4. Continuing vancomycin despite resistance: For isolates with vancomycin MIC >2 μg/mL, alternative agents should be used 3

5. Ignoring renal function changes: Regular monitoring of renal function is essential to prevent nephrotoxicity 1

By following these evidence-based dosing recommendations and monitoring guidelines, clinicians can optimize vancomycin therapy while minimizing the risk of treatment failure and adverse effects.