Dosage per Kilogram Calculator

How to calculate dosage per kilogram?

The weight-based method is the gold standard for determining medication amounts in clinical settings. By factoring in a patient's body mass, healthcare providers can customize the concentration of a drug to provide the therapeutic benefit while minimizing the risk of adverse side effects or toxicity.

Total Dose (mg) = Weight (kg) × Dosage (mg/kg)

Using the dosage calculator: an example

Consider a 70kg adult who has been prescribed a specific medication. The doctor's prescription indicates a dosage of 5mg per kilogram of body weight.

Step-by-step calculation:

1. Weight-to-Dose Conversion: Multiply the weight (70kg) by the dosage (5mg/kg) to determine a total of 350mg of medication.
2. Volume Calculation: If the liquid concentration is 10mg/mL, divide the total dose (350mg) by the concentration (10mg/mL) to find a required volume of 35mL.

Frequently Asked Questions

Why is dosage calculated by weight? It ensures that the drug concentration in the patient's bloodstream remains consistent, regardless of their physical size or age. This is particularly vital for medications with a narrow safety margin.

How do I convert lbs to kg? Divide your weight in pounds by 2.2046 to find the equivalent in kilograms (for example, 154 lbs is 70 kg).

What if my medication is a pill? After calculating the total milligrams needed, divide that number by the strength of a single pill (e.g., 100mg per tablet) to find out how many tablets to take.