Herbal medicine is a major component in Indian system of medicine , and a common element in Siddha, Ayurvedic, homeopathic, naturopathic, traditional Chinese medicine, and native American medicine. According to WHO herbal medicine is defined, herbal medicines as finished labeled medicinal product that contain active ingredients, aerial or underground parts of the plant or other plant material or combinations (WHO, 1998). In fact, according to the World Health Organization, approximately 25% of modern drugs used in the United States have been derived from plants. It is estimated that the global traditional medicine market is growing at the rate of 7 - 15 per cent annually.