Why Pediatric Dosing Is Different
Children are not simply small adults when it comes to medication dosing. Their bodies process medications differently, and doses must be carefully calculated based on factors like weight. The PTCE may include questions about pediatric dosing concepts and the calculations involved.
Weight-Based Dosing
Most pediatric medications are dosed based on the child's weight, typically expressed as milligrams per kilogram (mg/kg). To calculate a dose, you need to know the child's weight in kilograms and the prescribed dose in mg/kg. If a child weighs 20 kg and the dose is 10 mg/kg, the dose is 200 mg.
Converting Pounds to Kilograms
Since many patients' weights are recorded in pounds, you often need to convert. The conversion factor is 1 kg = 2.2 lb. To convert pounds to kilograms, divide the weight in pounds by 2.2. This is a common calculation on the PTCE.
Common Pediatric Dosage Forms
- Oral liquids (suspensions and solutions) - most common for young children
- Chewable tablets - for children who can safely chew but prefer not to swallow tablets
- Orally disintegrating tablets - dissolve on the tongue without water
Reconstitution
Many pediatric antibiotics come as powders that must be reconstituted with water before dispensing. The reconstituted suspension has a limited stability period and usually requires refrigeration. Knowing the reconstitution process and storage requirements is relevant to both the PTCE and daily practice.
Safety Considerations
Pediatric dosing errors can be especially dangerous because children are more sensitive to incorrect doses. Always double-check weight-based calculations, ensure the correct concentration is used, and verify that the dispensed volume makes sense for the calculated dose.