what is apparent volume of distribution? why we call in apparent? in which part of pharmacokinetic?

Answer 1

Pharmacokinetics deals with the location, distribution and effects of drugs over time.

The apparent volume of distribution is a theoretical pattern of drug distribution which is used to explain the relationship of of the amount of drug in the blood or plasma and how this changes over time.

It is called apparent because it is theoretical. It is a calculated value which is not based upon measuring the volumes of blood or tissues and knowing the concentrations of the drug by summing all the measurements.