The pediatric dose for acetaminophen is 10-15 mg/kg. The patient weighs 39 lbs. Which dose is safe for this patient?

The pediatric dose for acetaminophen is 10-15 mg/kg. The patient weighs 39 lbs. Which dose is safe for this patient?

• A. 225 mg
• B. 150 mg
• C. 300 mg
• D. 350 mg

Answer: (A)

Dosing kids by mg/kg means you multiply the child’s weight by the dose per kilogram to get a safe per-dose amount. First convert weight to kilograms: 39 lb ÷ 2.2046 ≈ 17.7 kg. The safe per-dose range is 10–15 mg per kg, so the low end is 10 × 17.7 ≈ 177 mg and the high end is 15 × 17.7 ≈ 265 mg. Any single dose should fall between about 177 and 265 mg. The 225 mg dose fits this range, while 150 mg is too low and 300 mg or 350 mg exceed the upper limit. Therefore, 225 mg is safe for this patient.

Dosing kids by mg/kg means you multiply the child’s weight by the dose per kilogram to get a safe per-dose amount. First convert weight to kilograms: 39 lb ÷ 2.2046 ≈ 17.7 kg. The safe per-dose range is 10–15 mg per kg, so the low end is 10 × 17.7 ≈ 177 mg and the high end is 15 × 17.7 ≈ 265 mg. Any single dose should fall between about 177 and 265 mg. The 225 mg dose fits this range, while 150 mg is too low and 300 mg or 350 mg exceed the upper limit. Therefore, 225 mg is safe for this patient.