A medication requires 2 mg per kilogram of body weight. How many milligrams should be administered to a 70 kg patient?

A medication requires 2 mg per kilogram of body weight. How many milligrams should be administered to a 70 kg patient?

• A. 140 mg
• B. 120 mg
• C. 150 mg
• D. 160 mg

Answer: (A)

Weight-based dosing multiplies the amount of drug per unit of body weight by the patient’s weight. Here, the dose is 2 mg for every kilogram, and the patient weighs 70 kilograms. So, 2 mg/kg × 70 kg = 140 mg. The kilograms cancel, leaving milligrams as the total dose. Therefore, the patient should receive 140 mg. (Other options would correspond to different weights.)

Weight-based dosing multiplies the amount of drug per unit of body weight by the patient’s weight. Here, the dose is 2 mg for every kilogram, and the patient weighs 70 kilograms. So, 2 mg/kg × 70 kg = 140 mg. The kilograms cancel, leaving milligrams as the total dose. Therefore, the patient should receive 140 mg. (Other options would correspond to different weights.)