Pharmacokinetics involves the study of absorption, distribution, metabolism and excretion (ADME) processes of drugs that is essential for drug discovery and development.These processes are mediated by drug-metabolizing enzymes and transporters expressed in various tissues including the small intestine, liver and kidney, which may limit or enhance the systemic and target organ exposure to a drug as well as other pharmacokinetic properties such as bioavailability, volume of distribution, clearance and half-life.