Paracetamol (Acetaminophen) Dosing for an 8-Month-Old Weighing 11.7 kg
For an 8-month-old infant weighing 11.7 kg, administer paracetamol 10-15 mg/kg per dose every 4-6 hours, which equals 117-175 mg per dose (maximum 4-5 doses per 24 hours, not exceeding 75 mg/kg/day or approximately 880 mg/day total). 1
Specific Dose Calculation
- Weight-based calculation: 11.7 kg × 10-15 mg/kg = 117-175 mg per dose 1
- Practical dosing: Most commonly, use 120-160 mg per dose for ease of measurement with standard syrup formulations 1
- Frequency: Every 4-6 hours as needed, with minimum 4-hour intervals between doses 1
- Maximum daily dose: Do not exceed 75 mg/kg/day (approximately 880 mg/day for this child) 1
Syrup Formulation and Administration
- Standard concentration: Paracetamol syrup typically comes as 120 mg/5 mL (24 mg/mL) or 160 mg/5 mL (32 mg/mL) 1
- For 120 mg/5 mL formulation: Give 5-6.5 mL per dose (120-156 mg) 1
- For 160 mg/5 mL formulation: Give 3.75-5 mL per dose (120-160 mg) 1
Critical Safety Parameters
- Maximum single dose: 15 mg/kg (175 mg for this child) 1
- Maximum daily doses: 4-5 doses per 24 hours 1
- Minimum dosing interval: 4 hours between doses 1
- Absolute maximum daily limit: Never exceed 75 mg/kg/day, as hepatotoxicity risk increases substantially above therapeutic dosing 2, 3
Important Clinical Caveats
- Hepatotoxicity risk: The toxic metabolite NAPQI causes liver damage when glutathione stores are depleted, which occurs with overdosing 2
- Plasma concentration threshold: Toxicity is unlikely unless plasma levels exceed 150 mcg/mL, far above the 5-20 mcg/mL achieved with therapeutic doses 2
- Avoid chronic overuse: While acute therapeutic use is safe, ensure parents understand proper dosing intervals and maximum daily limits 3
- No dose adjustment needed: This 8-month-old's weight (11.7 kg) is appropriate for age, requiring no special considerations 4
Practical Prescribing Example
Prescription: Paracetamol syrup 120 mg/5 mL
- Dose: Give 5 mL (120 mg) every 4-6 hours as needed for fever or pain
- Maximum: Do not give more than 5 doses in 24 hours
- Instructions: Measure dose carefully with provided syringe or measuring cup; never exceed recommended dose 1