The physician has ordered erythromycin 40 mg/kg/day po q6h for a child who weighs 33 pounds. Refer to the label shown in the figure. How much will you administer per dose?

Question

A. 2.5 mL
B. 3.25 mL
C. 3.75 mL
D. 4.25 mL
E. 4.5 mL

Answer 1

C. 3.75 mL
The child weighs 33 lb ¸ 2.2 kg/lb = 15 kg. The total dose per day = 40 mg x 15 kg = 600 mg per day. Divided into four doses per day, each dose equals 600 mg/4 = 150 mg/dose. D = 150 mg, H = 200 mg, and Q = 5 mL; 150 mg/200 mg x 5 mL = 3.75 mL.