How to Calculate the Volume of Distribution

Though a mathematical term, it is essential for pharmacists and doctors to know how to calculate the volume of distribution. The volume of distribution is a pharmacological calculation used to determine the distribution of a medication in the blood's plasma. It is important for medical personnel to know this calculation because every individual's distribution is unique. Accordingly, the volume can change if a person has liver failure, renal failure and/or dehydration. The equation is V = X/C, or volume equals amount over concentration.

Instructions

• 1

  Inject the person with medicine intravenously and measure the concentration of plasma immediately after injection.

• 2

  Make sure the two variables X and C are measured in comparable measurement systems. The best system to use for this equation is the metric system. It is not helpful to mix systems; for example, dividing liters into ounces.

• 3

  Divide the amount (X) over the concentration (C).