Rhubarb is a perennial herb of Polygonaceae family. It consists of the dried rhizomes of R. emodi and R. webbianum and other species of Rheum. Mostly three main types of Rhubarb viz., the Chinese Rhubarb, the Indian or Himalayan Rhubarb and the Rhaphontic Rhubarb are found. The commercial Rhubarb known as Chinese, Russian, Turkish and East Indian, is said to be obtained from the R. officinale and R. palmataum but Chinese rhubarb is the best among them. It is of saffron colour, has a fractured surface, and is friable. In India it is distributed in the Himalayas from Kashmir to Sikkim at altitudes of 3, 300-5, 200 mts. It is also cultivated in Assam. It has been used for centuries in Unani System of Medicine for its effect as a Purgative, Resolvent, Liver Tonic, Anti-inflammatory, Stomachic, Diuretic and Emenagogue and Deobstruent