Which statement correctly distinguishes dosage and dose?

• A. Dosage is the total amount per animal.
• B. Dose is the amount per unit weight.
• C. Dosage is the amount per unit weight.
• D. Dose and dosage are interchangeable.

Answer: (C)

The key idea is that dosage standardizes the amount by body weight, while the dose is the actual amount given. Dosage is expressed as an amount per unit body weight (for example, mg per kilogram). This allows you to scale the amount to animals of different sizes. The dose is the total amount administered to the animal (the actual mg or g given). For instance, with a dosage of 5 mg/kg and a 10 kg animal, you would administer a dose of 50 mg. That shows why dosage is the per‑weight measure, while the dose is the total amount delivered. The other statements mix these concepts: the total amount per animal is the dose, not the dosage; the dose is not per unit weight; and the two terms aren’t strictly interchangeable.