Pharmacology is the science that deals with drugs. Pharmacology consists of detailed study of drugs, particularly drugs action on living animals, tissues or organs. The action of drugs may be beneficial or harmful. Pharmacology is the science in which we study the response of living animals to chemicals or drugs. Pharmacology is defined as the study of the effects of drugs on the structures and metabolism of naturaltissue.Pharmacology can be defined as the study of the manner in which the functions of living system is affected or influenced by chemicals.This subject deals with the properties and effects of drugs and in broad sense, it can be defined as the study of interactions between chemical substances and biological systems. While defining in broad sense, it includes the knowledge of the history, source, physical and chemical properties, compounding, bio-chemical and physiological effects, mechanism of action, absorption, distribution, metabolism, excretion and therapeutic and other effects of drugs.

Homosapiens being the intelligent most among the species evolved, based on the principles of “necessity” and “trial” could observe effectiveness of many plants in relief for his pains and sufferings. The primitive (early) history of the causative agents of diseases included wrong Gods, spirits witches and other evil influences.
The form of therapy was incantation, prayer and ceremony designed to appease the evil agents of the diseases. They were using sacrifice of animals, individuals and prayers.The tribal leaders were known as medicine men or the expert or witch doctors (Ojha), were very powerful men and leader in such all ceremonies. In addition, they had knowledge about certain plants and animal products to be used in the treatment of certain diseases. The first treatise on medicine was undoubtedly the Ayurveda in India and that is at least 500 years ahead of the Greek Medicine.The medical literature was related to metaphysics, hypnotism etc. and belief in supernatural agencies as the cause and cure of diseases. Thus, in India, this was originally a part of the fourth Veda called the Atharva Veda. The real father of Indian Medicine was Atrya with his distinguished disciples-Agnivesha, Bhala, Jatukarana, parasara, Harita and Ksharapani.Works of Bhala and Harita are still available in fragments and those of Agnivesha were edited by Charaka which stand unsurpassed as a standard and authoritative book on Ayurveda even to day, other works are yet untraced. The next outstanding personality in Indian medicine was Susrutha whose works stand second to Charaka (a surgeon). He mentioned many instruments and techniques.

Started with Oswald Schmiedeberg (1838-1921). He was excellent teacher of Pharmacology and attracted many persons to study this subject. Like other experimental sciences, Pharmacology, too, is highly dependent upon development in other branches of science.Spectacular developments in physiology, biochemistry, organic chemistry and molecular biology have greatly contributed in advancement of pharmacology. Conversion of the old pharmacology into modern pharmacology is fairly recent and probably started taking shape following introduction of experimental procedures in animals by Francois Megendie (1783-1855) and Claude Bernard (1813-1978).Oswald Schmiedeberg (1838-1921) introduced the technique of per-fusing isolated organs and study the effects of drugs on them. Abel, Cushny, Gottlieb and a galaxy of his other students popularized the expertise in their respective, countries. Thus Oswald become popular as ‘Father of modern Pharmacology’.

Pharmacology is benefited by the prepared mind. You need to know what you are looking for.