Pharmacology Teaching and Research

Online Lecture: Pharmacokinetics.


Bioavailability and Distribution of Drugs

Drug distribution refers to the movement of a drug to and from the blood and various tissues of the body (for example, fat, muscle, and brain tissue) and the relative proportions of drug in the tissues. 

After a drug is absorbed into the bloodstream, it rapidly circulates through the body.


 Bioavailability is a subcategory of absorption and is the fraction of an administered dose of unchanged drug that reaches the systemic circulation, one of the principal pharmacokinetic properties of drugs. 

There are many recent advances and factors affecting bioavailability

These factors include:


Food Effect

Drug metabolism/ biotransformation

Energy dependent efflux transporters

Physico-chemical factors

First pass metabolism

CYP450 isozymes.

Click below for a Presentation - Bioavailability and Distribution of Drugs.



Bioavailability of Drugs: