Ampicillin-Sulbactam Dosing for Pediatric Patients
For pediatric patients, ampicillin-sulbactam should be dosed at 100-200 mg ampicillin/kg/day divided every 6 hours, with infants receiving 100-150 mg ampicillin/kg/day divided every 6 hours. 1
Standard Dosing Recommendations
Infants
- 100-150 mg ampicillin/kg/day divided every 6 hours 1
- This translates to approximately 25-37.5 mg ampicillin/kg/dose every 6 hours
Children (Beyond Infancy)
- 100-200 mg ampicillin/kg/day divided every 6 hours 1
- This translates to approximately 25-50 mg ampicillin/kg/dose every 6 hours
- The sulbactam component is administered in a 2:1 ratio (ampicillin:sulbactam) 2
Optimized Dosing for Severe Infections
For empiric therapy of community-acquired pneumonia or severe infections, the higher end of the dosing range (75 mg/kg four times daily, equivalent to 300 mg/kg/day) provides better pharmacodynamic coverage against common respiratory pathogens. 3
- The FDA-approved maximum dosage of 75 mg/kg four times daily achieves adequate coverage against Streptococcus pneumoniae (MIC90 = 2 μg/mL) and Haemophilus influenzae (MIC90 = 4 μg/mL) 3
- Lower dosing of 45 mg/kg three times daily may be insufficient for empiric therapy when MIC values are elevated 3
Clinical Efficacy Data
The combination demonstrates excellent clinical outcomes in pediatric populations:
- 98.7% cure rate across various pediatric infections including skeletal, intrathoracic, and soft tissue infections 4
- Well-tolerated with minimal adverse effects (only 1 rash reported in 78 patients that did not require discontinuation) 4
- Treatment duration typically ranges from 8-23 days depending on infection severity 4
Pharmacokinetic Considerations
Age does not significantly affect the pharmacokinetics of ampicillin-sulbactam in children aged 1-12 years, allowing for weight-based dosing without age-specific adjustments. 2, 3
- Mean half-life: 0.77 hours for ampicillin and 0.81 hours for sulbactam 2
- Peak serum concentrations: 177-200 μg/mL for ampicillin and 82-102 μg/mL for sulbactam 2
- Pharmacokinetics in pediatric patients are comparable to adults 2
Important Clinical Caveats
- Neonatal dosing differs significantly: For neonates, refer to ampicillin dosing guidelines which vary by postnatal age and weight, as specific ampicillin-sulbactam neonatal data is limited in the guidelines 1
- The combination should be dosed based on the ampicillin component, with sulbactam automatically included in the 2:1 fixed ratio 2
- For infections requiring higher ampicillin doses (such as meningitis), consider using ampicillin alone rather than ampicillin-sulbactam to achieve necessary CNS penetration 5