Understanding Medication Dosage
Medication dosage is the prescribed amount of medicine a patient should receive. While physicians typically determine dosages, medical assistants need to understand what factors affect dosing and how to calculate the correct amounts.
Several key factors influence dosage determination. Age is crucial—patients between 20-60 years typically receive standard adult doses, while pediatric and geriatric patients need customized amounts. Weight also matters significantly, with dosages often calculated based on body surface area (BSA) or kilograms of body weight for patients outside the typical 150-pound range.
Other important considerations include kidney disease, multiple health conditions, disease severity, medical history, allergies, and pregnancy status. Medical assistants often need to calculate how to administer prescribed dosages using available medication forms.
Pro Tip: When calculating medication dosages using proportions, always ensure all measurements are converted to the same unit (like milligrams or grams) before solving the equation.
Most dosage calculations use proportions, which are equations showing equality between two ratios. The key rule is that all measurements must be in the same units—this creates a "parallel proportion." For example, to solve a proportion with grams and milligrams, you must first convert them to the same unit.