A nurse is preparing to administer prochlorperazine 0.13 mg/kg IM to an adolescent who weighs 103 lb. Available is prochlorperazine injection 5 mg/mL. How many mL should the nurse administer per dose? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)

To calculate the dosage of prochlorperazine for the adolescent, first convert the weight from pounds to kilograms, knowing that 1 kilogram equals 2.2 pounds. The adolescent weighs 103 lb, which is approximately 46.82 kg (103 ÷ 2.2). Next, multiply the weight in kilograms by the dosage prescribed, which is 0.13 mg/kg. This results in a total dosage of 6.09 mg (46.82 kg × 0.13 mg/kg). Finally, divide the total dosage by the concentration of the available medication to find out how many mL to administer. The available prochlorperazine injection has a concentration of 5 mg/mL, so you would administer 1.22 mL (6.09 mg ÷ 5 mg/mL). Rounded to the nearest tenth, the nurse should administer 1.2 mL per dose.