A medication is dosed at 1.5 mg/kg. The patient weighs 8 kg. What is the dose?

A medication is dosed at 1.5 mg/kg. The patient weighs 8 kg. What is the dose?

• A. 9 mg
• B. 11 mg
• C. 12 mg
• D. 14 mg

Answer: (C)

When dosing by mg per kilogram, multiply the dose per kilogram by the patient's weight to get the total dose. Here, 1.5 mg/kg × 8 kg equals 12 mg. So the total dose is 12 mg. If you test the other numbers, they correspond to different per-kilogram doses (for example, 9 mg is 1.125 mg/kg, 11 mg is about 1.375 mg/kg, and 14 mg is 1.75 mg/kg), which don’t match the prescribed 1.5 mg/kg.

When dosing by mg per kilogram, multiply the dose per kilogram by the patient's weight to get the total dose. Here, 1.5 mg/kg × 8 kg equals 12 mg. So the total dose is 12 mg. If you test the other numbers, they correspond to different per-kilogram doses (for example, 9 mg is 1.125 mg/kg, 11 mg is about 1.375 mg/kg, and 14 mg is 1.75 mg/kg), which don’t match the prescribed 1.5 mg/kg.