What is the maximum dose of vancomycin per dose?

Maximum Dose of Vancomycin Per Dose

The maximum dose of vancomycin per dose is 2 grams, regardless of weight-based calculations. 1, 2

Dosing Guidelines for Adults

Vancomycin dosing follows these principles:

• Standard dosing: 15-20 mg/kg/dose (actual body weight) every 8-12 hours in patients with normal renal function 1
• Maximum per dose: Not to exceed 2 g per dose, even with weight-based calculations 1, 2
• Loading dose: 25-30 mg/kg (actual body weight) may be considered for seriously ill patients (sepsis, meningitis, pneumonia, endocarditis) 1
• Infusion time: When individual doses exceed 1 g (e.g., 1.5 g or 2 g), extend infusion time to 1.5-2 hours 1
• Infusion rate: 10 mg/min or less is associated with fewer infusion-related adverse reactions 2

Special Considerations

For Serious Infections

• Target trough concentrations of 15-20 μg/mL for serious infections such as:
  • Bacteremia
  • Infective endocarditis
  • Osteomyelitis
  • Meningitis
  • Pneumonia
  • Severe skin/soft tissue infections (e.g., necrotizing fasciitis) 1

For Less Severe Infections

• For most patients with skin/soft tissue infections who have normal renal function and are not obese:
  • Traditional doses of 1 g every 12 hours are adequate
  • Trough monitoring not required 1

For Obese Patients

• Morbidly obese patients may require more frequent dosing (every 8 hours instead of every 12 hours) to maintain therapeutic trough concentrations 3
• Continue to use actual body weight for calculations, but never exceed 2 g per dose

Monitoring Recommendations

• Trough concentrations should be obtained at steady state, prior to the fourth or fifth dose 1
• Monitoring of peak vancomycin concentrations is not recommended 1
• Trough monitoring is especially important for:
  • Serious infections
  • Morbidly obese patients
  • Patients with renal dysfunction
  • Patients with fluctuating volume of distribution 1

Pediatric Considerations

• Children with serious infections: 15 mg/kg/dose every 6 hours 1
• Target trough concentrations of 15-20 μg/mL should be considered for serious pediatric infections 1
• Neonates and infants under 1 month may require lower total daily doses and longer dosing intervals 2

Common Pitfalls to Avoid

1. Underdosing obese patients: Using ideal body weight instead of actual body weight can lead to subtherapeutic levels
2. Inadequate loading doses: Failure to use loading doses (25-30 mg/kg) in critically ill patients may delay achieving therapeutic concentrations
3. Infusion-related reactions: Administering vancomycin too rapidly increases risk of "red man syndrome" - consider antihistamine premedication and slower infusion rates for loading doses 1
4. Ignoring renal function: Failure to adjust dosing in renal impairment increases toxicity risk
5. Continuing vancomycin despite poor response: If patient has not had clinical or microbiologic response despite adequate debridement and removal of other infection foci, consider alternative agents regardless of MIC 1

Remember that while the maximum dose is capped at 2 g per dose, the frequency of administration may need to be increased to achieve therapeutic targets in patients with enhanced clearance, such as those with sepsis or augmented renal clearance.