traditionally, physicians rely on medical knowledge learned or acquired through practice to make a correct decision in diagnosis of diseases and affected medications. progress in knowledge base systems and related information technology changed this situation by providing huge amount of medical information that can support physicians in the decision making. integrating this great amount of information to retrieve the superlative results is however a demanding job. by introducing the concepts of semantic web, the sources of medical knowledge have amended to acquire the advantages of this concept and its technologies in gathering and representing the information and recommending superior decision from comprehensive information. particularly, ontologies are recognized to enhance the efficiency of information management significantly and improve the dependability of communication especially when heterogeneous actors and diverse environments are involved.