Neonatal dosing
Aciclovir IV
| Age | Starting dose |
|---|---|
| Neonates younger than 34 weeks post menstrual age | 20mg/kg/dose every 12 hours |
| Neonates 35 weeks post menstrual age or older | 20mg/kg/dose every 8 hours |
Ampicillin IV (or Amoxycillin IV)
| Age | Post natal age | Starting dose |
|---|---|---|
| Neonates < 29 weeks post menstrual age | Postnatal age 0 to 28 days | 50mg/kg/dose every 12 hours |
| Neonates < 29 weeks post menstrual age | Postnatal age > 28 days | 50mg/kg/dose every 8 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age 0 to 14 days | 50mg/kg/dose every 12 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age > 14 days | 50mg/kg/dose every 8 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age 0 to 7 days | 50mg/kg/dose every 12 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age > 7 days | 50mg/kg/dose every 8 hours |
| Neonates > 45 weeks post menstrual age | All | 50mg/kg/dose every 6 hours |
Benzylpenicillin IV
| Age | Post natal age | Starting dose |
|---|---|---|
| Neonates <29 weeks post menstrual age | Postnatal age 0 to 28 days | 60mg/kg/dose every 12 hours |
| Neonates <29 weeks post menstrual age | Postnatal age >28 days | 60mg/kg/dose every 8 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age 0 to 14 days | 60mg/kg/dose every 12 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age >14 days | 60mg/kg/dose every 8 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age 0 to 7 days | 60mg/kg/dose every 12 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age > 7 days | 60mg/kg/dose every 8 hours |
| Neonates > 45 weeks post menstrual age | ALL | 30-60mg/kg/dose every 6 hours |
Cefotaxime IV
| Age | Starting dose | |
|---|---|---|
| Neonates <29 weeks post menstrual age | Postnatal age 0 to 28 days | 50mg/kg/dose every 12 hours |
| Neonates <29 weeks post menstrual age | Postnatal age >28 days | 50mg/kg/dose every 8 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age 0 to 14 days | 50mg/kg/dose every 12 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age >14 days | 50mg/kg/dose every 8 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age 0 to 7 days | 50mg/kg/dose every 12 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age >7 days | 50mg/kg/dose every 8 hours |
| Neonates >45 weeks post menstrual age | All | 50mg/kg/dose every 6 hours |
Flucloxacillin IV
| Post menstrual age | Post natal age | Starting dose |
|---|---|---|
| Term/Premature neonates | Postnatal age 0 to 7 days | 50mg/kg/dose every 12 hours |
| Term/Premature neonates | Postnatal age 8 to 20 days | 50mg/kg/dose every 8 hours |
| Term/Premature neonates | Postnatal age 21 to 28 days | 50mg/kg/dose every 6 hours |
Gentamicin IV
- Therapeutic drug monitoring required**
| Age | Starting dose | |
|---|---|---|
| Neonates younger <30 weeks post menstrual age | Postnatal age 0 to 14 days | 5mg/kg/dose every 48 hours** |
| Neonates younger < 30 weeks post menstrual age | Postnatal age 15 to 28 days | 5mg/kg/dose every 36 hours** |
| Neonates 30 to 34 weeks post menstrual age | Postnatal age 0 to 28 days | 5mg/kg/dose every 36 hours** |
| Neonates 35 weeks post menstrual age or older | Postnatal age 0 to 28 days | 5mg/kg/dose every 24 hours** |
Metronidazole IV
| Age | Starting dose | |
|---|---|---|
| Neonates <29 weeks post menstrual age | Postnatal age 0 to 28 days | 7.5mg/kg/dose every 48 hours |
| Neonates <29 weeks post menstrual age | Postnatal age >28 days | 7.5mg/kg/dose every 36 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age 0 to 14 days | 7.5mg/kg/dose every 24 hours |
| Neonates 30 to 36 weeks post menstrual age | Postnatal age >14 days | 7.5mg/kg/dose every 12 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age 0 to 7 days | 7.5mg/kg/dose every 24 hours |
| Neonates 37 to 44 weeks post menstrual age | Postnatal age > 7 days | 7.5mg/kg/dose every 12 hours |
| Neonates >45 weeks post menstrual age | All | 7.5mg/kg/dose every 8 hours |
Vancomycin IV
Therapeutic drug monitoring required**
| Age | Starting dose | |
|---|---|---|
| Neonates younger ≤ 29 weeks post menstrual age | Post natal age 0 to 14 days | 15mg/kg/dose IV 18 hourly** |
| Neonates younger ≤ 29 weeks post menstrual age | Post natal age >14 days | 15mg/kg/dose IV 12 hourly** |
| Neonates >29 to 36 weeks post menstrual age | Post natal age 0 to 14 days | 15mg/kg/dose IV 12 hourly** |
| Neonates >29 to 36 weeks post menstrual age | Post natal age >14 days | 15mg/kg/dose IV 8 hourly** |
| Neonates 36 to 44 weeks post menstrual age | Post natal age 0 to 7 days | 15mg/kg/dose IV 12 hourly** |
| Neonates 36 to 44 weeks post menstrual age | Post natal age >7days | 15mg/kg/dose IV 8 hourly** |
| Neonates 44 weeks post menstrual age or older | All ages | 15mg/kg/dose IV 6 hourly** |
Definitions
Postmenstrual age:
The time elapsed between the first day of the last menstrual period and birth (gestational age) plus the time elapsed after birth (postnatal age).
The time elapsed between the first day of the last menstrual period and birth (gestational age) plus the time elapsed after birth (postnatal age).
Renal function and drug elimination are most strongly correlated with Postmenstrual Age.
