What dose in milligrams is safest for this child? Archie who weighs 44 lb has been given an order for amoxicillin 500 mg b.i.d. The drug text notes that the daily dose of amoxicillin is 50 mg/kg/day in two divided doses.
First. calculate the childs weight in kg: 44/2.2 = 20 kg. Then calculate the appropriate daily dose according to the drug text: 50 mg/kg/day = 50 mg x 20 kg = 1.000 mg/day. the abbreviation b.i.d. means twice daily; therefore 1.000 divided by 2 equals 500 mg.