Volume of Distribution
VdDefinition
A theoretical volume that relates the total amount of drug in the body to its plasma concentration. A large Vd indicates the drug distributes extensively into tissues, while a small Vd suggests the drug remains primarily in the blood.
Example
Chloroquine has a very high Vd (~200 L) because it concentrates in tissues, while warfarin has a low Vd (~8 L) because it stays mostly in the blood bound to albumin.
Related Terms
Mentioned in Guides
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