Maximum Dose of Ampicillin-Sulbactam in Pediatric Patients
The maximum dose of ampicillin-sulbactam in pediatric patients is 300 mg/kg/day (200 mg ampicillin/100 mg sulbactam per kg/day) divided every 6 hours, with the total sulbactam dose not exceeding 4 grams per day. 1
Age-Specific Dosing Guidelines
Infants and Children Under 40 kg
- For infants, the recommended dose is 100-150 mg ampicillin/kg/day divided every 6 hours 2
- For children, the recommended dose is 100-200 mg ampicillin/kg/day divided every 6 hours 2
- The FDA-approved maximum daily dose is 300 mg/kg/day administered via intravenous infusion in equally divided doses every 6 hours, which represents the total ampicillin content plus sulbactam content (200 mg ampicillin/100 mg sulbactam per kg/day) 1
Children 40 kg or Greater
- Pediatric patients weighing 40 kg or more should be dosed according to adult recommendations 1
- Adult dosing ranges from 1.5 g (1 g ampicillin/0.5 g sulbactam) to 3 g (2 g ampicillin/1 g sulbactam) every 6 hours 1
- The total dose of sulbactam should not exceed 4 grams per day regardless of weight 1
Critical Dosing Considerations
Route of Administration
- The safety and efficacy of ampicillin-sulbactam administered via intramuscular injection in pediatric patients have not been established 1
- Intravenous administration is the recommended route for pediatric patients, given either by slow IV injection over 10-15 minutes or as an infusion over 15-30 minutes 1
Duration of Therapy
- The course of intravenous therapy should not routinely exceed 14 days 1
- In clinical trials, most children received a course of oral antimicrobials following initial treatment with intravenous ampicillin-sulbactam 1
Pharmacokinetic Support for Dosing
- Pharmacokinetic studies demonstrate that doses of 40-80 mg/kg every 6 hours achieve adequate serum concentrations, with mean peak levels of 177-200 mcg/mL for ampicillin and 82-102 mcg/mL for sulbactam 3
- The mean half-life is approximately 0.77 hours for ampicillin and 0.81 hours for sulbactam in pediatric patients, comparable to adults 3
- Recent pharmacodynamic modeling suggests that 75 mg/kg four times daily (q.i.d.) may be optimal for empiric therapy of community-acquired pneumonia to achieve adequate PK/PD targets against common pathogens 4
Common Pitfalls to Avoid
- Do not exceed 4 grams per day of sulbactam component, even in larger children or adolescents 1
- Do not use intramuscular administration in pediatric patients, as safety and efficacy have not been established by this route 1
- Adjust dosing frequency in renal impairment according to creatinine clearance, extending intervals to every 12 hours for CrCl 15-29 mL/min or every 24 hours for CrCl 5-14 mL/min 1