Question

A nurse is preparing to administer chlorpromazine 0.55 mg/kg PO to an adolescent who weighs 110 lb. Available is chlorpromazine syrup 10 mg/5 mL. How many mL should the nurse administer?

A) 14 mL
B) 7 mL
C) 21 mL
D) 28 mL

Answer 1

To calculate the amount of chlorpromazine syrup to administer, convert the weight to kilograms and multiply by the dosage per kilogram. Then set up a proportion to convert milligrams to milliliters.

Step-by-step explanation:

To calculate the amount of chlorpromazine syrup that the nurse should administer, we need to first convert the weight of the adolescent from pounds to kilograms. There are 2.2 pounds in 1 kilogram, so the adolescent weighs approximately 50 kilograms (110 lb / 2.2 lb/kg). Next, we multiply the weight in kilograms by the dose of chlorpromazine per kilogram: 0.55 mg/kg * 50 kg = 27.5 mg. To find the amount of syrup to administer, we need to convert milligrams to milliliters. Since the syrup is 10 mg/5 mL, we can set up a proportion: 10 mg/5 mL = 27.5 mg/x mL.

Cross-multiplying, we get 10 mg * x mL = 5 mL * 27.5 mg. Dividing both sides by 10 mg, we find that x mL = 5 mL * 27.5 mg / 10 mg. Simplifying, x mL = 5 mL * 2.75 = 13.75 mL. Therefore, the nurse should administer approximately 14 mL of chlorpromazine syrup.