| | Infants ≤7 days of age | Infants 8 to 28 days of age | Infants 29 to 60 days of age | Infants and children >60 days of age | Nonpregnant adults |
| Ampicillin | Patients in whom CNS infection has been documented or not yet excluded: - 300 mg/kg per day IV in 3 divided doses
Patients in whom CNS infection has been excluded (weight-directed dosing)*: - Weight ≤2 kg: 100 mg/kg per day IV in 2 divided doses
- Weight >2 kg: 150 mg/kg per day IV in 3 divided doses
| Patients in whom CNS infection has been documented or not yet excluded: - 300 mg/kg per day IV in 4 divided doses
Patients in whom CNS infection has been excluded (weight-directed dosing)*: - Weight ≤2 kg: 150 mg/kg per day IV in 2 divided doses
- Weight >2 kg: 150 mg/kg per day IV in 3 divided doses
| Patients in whom CNS infection has been documented or not yet excluded: - 300 mg/kg per day IV in 4 divided doses
Patients in whom CNS infection has been excluded: - 200 mg/kg per day IV in 4 divided doses
| Patients in whom CNS infection has been documented or not yet excluded: - 300 to 400 mg/kg per day IV in 4 to 6 divided doses; maximum dose: 12 g per day
Patients in whom CNS infection has been excluded: - 200 mg/kg per day IV in 4 divided doses; maximum dose: 8 g per day
| 2 g IV every 4 hours |
| or |
| Penicillin G | Patients in whom CNS infection has been documented or not yet excluded: - 450,000 units/kg/day IV in 3 divided doses
Patients in whom CNS infection has been excluded: - 100,000 units/kg/day IV in 2 divided doses
| Patients in whom CNS infection has been documented or not yet excluded: - 400,000 to 500,000 units/kg/day IV in 4 divided doses
Patients in whom CNS infection has been excluded: - 150,000 units/kg/day IV in 3 divided doses
| Patients in whom CNS infection has been documented or not yet excluded: - 400,000 to 500,000 units/kg/day IV in 4 divided doses
Patients in whom CNS infection has been excluded: - 200,000 units/kg/day IV in 4 divided doses
| Patients in whom CNS infection has been documented or not yet excluded: - 400,000 to 500,000 units/kg per day IV in 4 to 6 divided doses; maximum dose: 24 million units per day; doses >400,000 units/kg per day are generally only used for infants <1 year of age
Patients in whom CNS infection has been excluded: - 250,000 to 300,000 units/kg/day IV in 4 to 6 divided doses; maximum dose: 24 million units per day
| 4 million units IV every 4 hours |
| plus (if CNS, bloodstream, or other serious infection) |
| | Infants ≤60 days of age | Infants and children >60 days of age | Nonpregnant adults |
| Gentamicin¶ | Gestational age <30 weeks: - Postnatal age ≤14 days: 5 mg/kg IV every 48 hours
- Postnatal age >14 days: 5 mg/kg IV every 36 hours
Gestational age 30 to 34 weeks: - Postnatal age ≤10 days: 5 mg/kg IV every 36 hours
- Postnatal age >10 to 60 days: 5 mg/kg IV every 24 to 36 hours
Gestational age ≥35 weeks: - Postnatal age ≤7 days: 4 mg/kg IV every 24 hours
- Postnatal age >7 to 60 days: 5 mg/kg IV every 24 hours
| 7.5 mg/kg per day IV in 3 divided doses | 5 mg/kg per day IV in 3 divided doses |
