Acetaminophen Dosing for a 3.799 kg Newborn
For a newborn weighing 3.799 kg, administer acetaminophen 10-15 mg/kg per dose every 4-6 hours as needed, which equals 38-57 mg per dose, with a maximum of 5 doses per 24 hours not exceeding 75 mg/kg/day (approximately 285 mg/day total). 1
Weight-Based Dose Calculation
The precise calculation for this 3.799 kg newborn is:
Practical dosing recommendation: Give 40-55 mg per dose for ease of measurement with standard infant formulations 1
Dosing Interval and Frequency
- Administer every 4-6 hours as needed for fever or pain 1
- Minimum interval between doses must be 4 hours 1
- Maximum of 4-5 doses in 24 hours 1
Formulation and Administration
- Acetaminophen infant drops typically come as 80 mg/0.8 mL (100 mg/mL) or 160 mg/5 mL (32 mg/mL) syrup 1
- For 80 mg/0.8 mL drops: Give 0.32-0.44 mL per dose (40-55 mg) 1
- For 160 mg/5 mL syrup: Give 1.25-1.7 mL per dose (40-54 mg) 1
- Always use the calibrated dropper or syringe provided with the product to ensure accurate dosing 1
Critical Safety Parameters
- Never exceed 15 mg/kg per single dose (57 mg for this infant) 1
- Never exceed 75 mg/kg/day total daily dose (285 mg/day for this infant) 1
- Never give doses more frequently than every 4 hours 1
- Acetaminophen overdose can cause severe hepatotoxicity and acute liver failure, even in infants, making strict adherence to dosing limits essential 2, 3
Common Pitfalls to Avoid
- Do not confuse infant drops (80 mg/0.8 mL) with children's syrup (160 mg/5 mL) - this concentration difference has led to serious overdoses 1
- Do not combine multiple acetaminophen-containing products without accounting for total daily dose 3
- Ensure parents understand the maximum daily dose - repeated supratherapeutic dosing over days can cause hepatotoxicity even when individual doses seem appropriate 2, 3
Practical Prescribing Example
Prescription: Acetaminophen infant drops 80 mg/0.8 mL