Pharmacokinetics is the study of the kinetics of drug absorption, distribution and elimination, which will determine the time-course of the drug profile in the body. While pharmacodynamics describes the relationship between the drug conc at the site of action and the observed pharmacological effect.

The pharmacokinetic properties of the drug determine the time course of the drug at the site of action. The pharmacodynamic models describe how the change in the drug profile at the site of action will be reflected on the observed drug effect. Linking the pharmacokinetics and pharmacodynamics of the drug allows prediction of the time course of the drug effect.