Acetaminophen Dosing for a 97-Pound Child
For a 97-pound (44 kg) child, administer 660 mg of acetaminophen (Tylenol 160 mg/5 mL suspension) per dose, which equals 20.6 mL of the suspension, given every 4–6 hours as needed, not exceeding 5 doses in 24 hours.
Weight-Based Calculation
- A 97-pound child weighs approximately 44 kg (97 lb ÷ 2.2 = 44 kg). 1
- The standard acetaminophen dose is 10–15 mg/kg per dose, with the higher end of this range (15 mg/kg) recommended for effective antipyresis and analgesia. 1, 2
- At 15 mg/kg: 44 kg × 15 mg/kg = 660 mg per dose. 1
- Using Tylenol 160 mg/5 mL suspension: 660 mg ÷ 160 mg = 4.125, then 4.125 × 5 mL = 20.6 mL per dose. 1
Dosing Interval and Maximum Daily Dose
- Administer every 4–6 hours as needed for fever or pain. 1
- Maximum daily dose is 60 mg/kg/day (44 kg × 60 = 2,640 mg/day), which translates to no more than 5 doses in 24 hours when using 660 mg per dose. 1
- Never exceed this maximum to prevent hepatotoxicity. 1
Why 15 mg/kg Is Preferred Over 10 mg/kg
- Pharmacokinetic modeling demonstrates that 10 mg/kg fails to achieve therapeutic plasma concentrations (10–20 μg/mL) needed for effective antipyresis in many children. 3
- A dose of 15 mg/kg reliably reaches therapeutic levels and provides consistent fever reduction for approximately 6 hours. 4, 2
- Clinical trials consistently show that 15 mg/kg produces superior temperature reduction compared to 10 mg/kg, with maximum effect occurring around 3 hours post-dose. 2
Special Considerations for This Weight Range
- Children weighing more than 40 kg can be dosed as adults according to some guidelines, but weight-based dosing (15 mg/kg) remains more precise and is preferred. 5, 6
- At 44 kg, this child falls just above the 40 kg threshold, making the calculated 660 mg dose appropriate and safe. 5
Formulation Considerations
- Oral suspension is absorbed more rapidly and provides more consistent response compared to rectal suppositories. 1
- Use an accurate measuring device (oral syringe or dosing cup) to ensure precise measurement of 20.6 mL. 6
Risk Factors That Would Require Dose Reduction
If this child has any of the following conditions, reduce the dose to 10 mg/kg (440 mg or 13.75 mL): 1
- Chronic malnutrition or fasting >8 hours without adequate caloric intake
- Concurrent use of cytochrome P450-inducing medications (e.g., isoniazid, phenytoin, carbamazepine)
- Pre-existing liver disease
These conditions increase hepatotoxicity risk by enhancing production of the toxic NAPQI metabolite or reducing hepatic reserve. 1
Common Pitfalls to Avoid
- Age-based dosing leads to underdosing in up to 30% of children—always use weight-based calculation. 3
- Do not rely on manufacturer's age-based recommendations on the bottle, which may provide inadequate doses for children at the upper end of weight ranges. 3
- Ensure parents understand the difference between infant drops (if still available) and children's suspension concentrations to prevent dosing errors. 7