How do you determine the appropriate pediatric dose for medications that require mg/kg dosing?

• A. Use the patient’s weight in kilograms and multiply by mg/kg; apply protocol maximums
• B. Use weight in pounds only
• C. Use age-based dosing
• D. Use a fixed adult dose

Answer: (A)

Start with the child’s weight in kilograms and the prescribed mg/kg dose. If the weight is given in pounds, convert it to kilograms (divide by 2.2). Multiply the weight in kilograms by the mg/kg dose to get the milligrams for that dose, then apply any protocol maximums per dose (and per day) to avoid overdosing. This weight-based approach accounts for the wide variation in pediatric sizes and how drug exposure scales with body mass. Age-based dosing or using a fixed adult dose can be inappropriate because they don’t reflect the child’s actual size or drug handling, increasing the risk of underdosing or toxicity. For example, a 12 kg child receiving 5 mg/kg would get 60 mg per dose, limited by any maximum dose if applicable.