Pharmacokinetics is the branch of pharmacology that studies the disposition of the active drug to specific tissues in the body (Kenakin, 2006). It is concerned with determining what happens to a drug once it gets in the body including the time needed for a drug to be absorbed, its distribution to organs and tissues, metabolism and excretion. Pharmacokinetics principles are the foundation for clinical pharmacokinetics which seeks to determine ways of enhancing the efficacy of drugs while reducing toxicity levels and potential harm to