Pharmacokinetics may be defined as the study of the dynamic movements of foreign chemicals (xenobiotics) during their passage through the body and as such encompass the kinetics of absorption, distribution, biotransformation/metabolism and excretion (ADME). It can simply be described as how the body handles xenobiotics. Pharmacokinetics uses (models) to describe the time course of ADME of xenobiotics in the body enabling us to better understand, interpret and even predict the nature and the extent of the biological effects (therapeutic or toxic) of xenobiotics