In a pediatric prescription, why can age not be solely relied upon?

In pediatric prescriptions, relying solely on age can be problematic because children grow and develop at different rates, which can significantly affect their physiological responses to medication. Age alone does not account for variations in body size, metabolic rate, and the developmental stage of organ systems, all of which can influence drug dosing and efficacy.

For example, a 5-year-old child might weigh significantly different amounts depending on their genetics, diet, and health status, leading doctors to consider weight or surface area to calculate appropriate medication dosages. This consideration is crucial since children metabolize drugs differently than adults, and a dosage based solely on age could lead to underdosing or overdosing. Therefore, the variability in individual development underscores the importance of using more precise measures, such as weight, when prescribing medications to ensure safety and effectiveness.