Kinetics of Drug Disposition and Pharmacologic Effect in Disease States.

The study of pharmacokinetics seeks to explain the time course of drug concentration in the body, while pharmacodynamics describes the drug effects once the drug has reached its site of action. The quantitative evaluation of drug action in vivo therefore requires the linkage of pharmacokinetics and pharmacodynamics. In addition, when the drug effect on the body is not directly measurable, for example with enzyme inhibition, the physiological consequences of this effect are often used as a measure of drug effect. Incorporation of what is known about the physiological regulation system into a physiological effect model can enhance not only the understanding of the pharmacodynamics of the drug, but also of the physiological process. In the present study, we have investigated the effects of disease states on the pharmacokinetics and pharmacodynamics of various drugs such as propranolol, ajmaline, and natriuretic peptides. As we learn more about the effects of diseases, age, gender and other individual characteristics on the pharmacokinetics and pharmacodynamics of drugs, it will become possible to make drug therapy more effective and safer.