Formula for Volume of Distribution
Volume of Distribution (Vd) of a drug is calculated as:
- Dose / plasma conc. — Correct Answer
- AUC / dose
- Plasma conc. / dose
- Dose × half-life
Explanation:
Correct Answer: Dose given / Concentration of drug in plasma
Volume of Distribution (Vd) = Dose given / Concentration of drug in plasma. It is the amount of body fluid that would be required if the drug were equally distributed throughout, giving the same concentration as found in plasma — an apparent, not a real volume.
Key Points on Vd
- Larger Vd → more drug distributed outside the plasma.
- Highly protein-bound and tissue-bound drugs have higher Vd.
- Drugs with higher Vd are preferred for treating infections in remote sites (skin, bone, muscle).
- Vd = Cl / β (where Cl is clearance and β is the elimination rate constant).
📚 About this Topic — Veterinary Pharmacology and Toxicology
This multiple choice question is from Veterinary Pharmacology and Toxicology, Veterinary Science. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Veterinary Pharmacology and Toxicology to strengthen your preparation.
