Quick antipyretic dosing

To calculate the mL of standard concentration ibuprofen (100 mg / 5 mL) or acetaminophen (160 mg / 5 mL) to give, take the child’s weight in kg and divide by 2.

mL of ibuprofen or acetaminophen = child’s weight in kg divided by 2

Don’t use for children > 40 kg for ibuprofen (as 20 mL = 400 mg is an appropriate maximum dose of ibuprofen)

The math:

Ibuprofen

weight (kg) x 10 mg/kg x 5 mL/100mg = weight (kg) x 1/2

Acetaminophen

weight (kg) x 15 mg/kg x 5mL/160mg = weight (kg ) x 0.47

0.47 is close enough to 1/2