Paracetamol IM Dosing for 9kg Infant
Intramuscular paracetamol is NOT recommended for routine use in pediatric patients, as this route is not standard practice and lacks robust safety/efficacy data in children.
Critical Issue with IM Route
- IM administration of paracetamol is not a standard route in pediatric practice and is not mentioned in current pediatric emergency medicine guidelines 1
- The evidence base focuses on oral, rectal, and intravenous routes only 2, 3, 4, 5
- IM injection can cause tissue necrosis and pain at the injection site, making it particularly unsuitable for children 1
Recommended Alternative Routes
Intravenous Route (Preferred Injectable Option)
If injectable paracetamol is truly needed, use IV administration instead:
- Dose: 7.5 mg/kg per dose for infants and children weighing less than 10 kg 2
- For a 9 kg infant: 67.5 mg IV (6.75 mL of 10 mg/mL solution) 2
- Can be given every 6 hours with maximum daily dose of 30 mg/kg/day 2
- Dilute in 0.9% normal saline or 5% dextrose if needed for smaller volumes 2
Oral Route (First-Line)
- Dose: 10-15 mg/kg every 4-6 hours 3, 6, 4
- For a 9 kg infant: 90-135 mg per dose
- Maximum daily dose: 60 mg/kg/day (540 mg/day for 9 kg infant) 3, 4
- Oral absorption is more predictable than rectal in this age group 5
Rectal Route (Alternative)
- Dose: 15-20 mg/kg per dose 5
- For a 9 kg infant: 135-180 mg per dose
- Absorption is slower and more erratic than oral, especially in infants 4, 5
Important Safety Considerations
- Hepatotoxicity risk occurs with chronic dosing exceeding 90-140 mg/kg/day for several days 3, 7
- Infants have reduced glucuronide conjugation but enhanced sulphation pathways, providing some protection 5
- Plasma concentration target: 10-20 mg/mL for analgesic/antipyretic effect 5
- Clearance is reduced in neonates and young infants, requiring dose adjustment 5
Clinical Bottom Line
Do not use IM paracetamol. If oral route is not feasible, use IV paracetamol at 7.5 mg/kg (67.5 mg for 9 kg infant) every 6 hours 2. If IV access is unavailable and oral administration is impossible, consider rectal administration at 15-20 mg/kg 5.