Pharmacology is a branch of pharmaceutical sciences which is concerned with the study of drug or medication action, where a drug can be broadly or narrowly defined as any man-made, natural, or endogenous molecule which exerts a biochemical or physiological effect on the cell, tissue, organ, or organism. Pharmacology is the study of the action of drugs on a biologic system. It incorporates components of medicine and biology. Pharmacodynamics, which in common usage is usually termed “pharmacology”, is concerned with the study of drug effects and how they are produced. The inception of Indian Pharmacological Society and International Union of Pharmacology is worth mentioning. Pharmacology is a medical science that forms a backbone of the medical profession as drugs form the corner stone of therapy in human diseases It is the study of drugs and how they affect the body.Pharmacology and Pharmacotherapeutics is the science of the therapeutic uses and the action of drug on biological systems.A pharmacology degree provides an understanding of medications, their sources, chemical properties, biological effects and therapeutic uses.It is underpinned by the basic science of pharmacology, with added focus on the application of pharmacological principles and methods in the real world.Pharmacology connects the gap between medical practice and laboratory science. It explains the way the living organisms react to chemical agents.