Vancomycin Dosing for Meningitis
For bacterial meningitis, administer vancomycin 15-20 mg/kg IV every 8-12 hours (typically every 12 hours in adults) in combination with a third-generation cephalosporin, targeting serum trough concentrations of 15-20 mg/L. 1, 2
Empiric Therapy Dosing
Vancomycin should never be used as monotherapy for meningitis due to poor CSF penetration and documented treatment failures. 1, 3 The standard empiric regimen includes:
- Vancomycin: 15-20 mg/kg IV every 12 hours (or every 8-12 hours) 1, 2
- Plus ceftriaxone: 2g IV every 12 hours OR cefotaxime 2g IV every 4-6 hours 1
- Add rifampin: 300-600 mg IV/PO every 12 hours if dual resistance to penicillin and cephalosporins is suspected 1, 2
Pathogen-Specific Adjustments
Pneumococcal Meningitis (Resistant Strains)
- Continue vancomycin 15-20 mg/kg IV every 12 hours plus ceftriaxone for penicillin/cephalosporin-resistant S. pneumoniae 1, 2
- Consider adding rifampin 600 mg PO/IV twice daily for highly resistant strains 1, 2
- Treatment duration: 10-14 days (extend to 14 days for resistant strains or delayed response) 2
Staphylococcal Meningitis (Including MRSA)
- Vancomycin 15-20 mg/kg IV every 8-12 hours 1, 2
- Add rifampin 300-450 mg twice daily for better CNS penetration 1, 2
- Treatment duration: Minimum 14 days 1, 2
Therapeutic Monitoring
Critical monitoring parameters to ensure adequate CNS penetration:
- Obtain trough levels before the 4th dose (at steady state) 2
- Target trough: 15-20 mg/L for meningitis 1, 2
- Monitor more frequently in patients with unstable renal function 2
- Research shows CSF penetration is approximately 48% in inflamed meninges versus only 18% in non-inflamed meninges 4
Pediatric Dosing
- Children: 15 mg/kg IV every 6 hours 1, 2
- Neonates <1 week: 10-15 mg/kg every 12 hours 1
- Neonates 1-4 weeks: 10-15 mg/kg every 8 hours 1
Important Clinical Considerations
When to Consider Alternative or Adjunctive Therapy
Intrathecal vancomycin (10 mg/day) may be considered in patients not responding to IV therapy alone, particularly in healthcare-associated meningitis with mild inflammation where CSF penetration is inadequate. 1, 5
Consider alternative agents if vancomycin MIC ≥2 mg/L, as target AUC/MIC ratios >400 may not be achievable with conventional dosing. 2
Common Pitfalls to Avoid
- Do not use vancomycin monotherapy: Always combine with a third-generation cephalosporin, as vancomycin alone has documented treatment failures 1, 3, 6
- Do not underdose: Standard dosing may result in subtherapeutic CSF levels, particularly in healthcare-associated meningitis with mild inflammation 7
- Do not delay rifampin addition: In highly resistant pneumococcal infections, add rifampin early if susceptibility testing confirms resistance 1, 2
- Monitor renal function: Vancomycin-induced nephrotoxicity is defined as ≥2-3 consecutive increases in serum creatinine (≥0.5 mg/dL or 150% from baseline) 2
Special Populations
Age >50 years or immunocompromised: Add ampicillin/amoxicillin 2g IV every 4 hours to cover Listeria monocytogenes in addition to vancomycin plus ceftriaxone. 1
Post-neurosurgical meningitis: Use the same vancomycin dosing regimen (15-20 mg/kg IV every 12 hours) for at least 10-14 days. 2