Rehmannia glutinosa is one of the 50 fundamental herbs used in traditional Chinese medicine, where it has the name Sheng Di huang. It is often sold as gān dì huáng, gān meaning "dried." One of the traditional uses in traditional Chinese medicine for Rehmannia glutinosa has been in the area of tinnitus and hearing loss. The plant seems to have efficacy in the scavenging of free radicals in vitro. This study however, does not report the effects of Rehmannia glutinosa in human subjects. A number of chemical constituents including iridoids, phenethyl alcohol, glycosides, cyclopentanoid monoterpenes, and norcarotenoids, have been reported from the fresh or processed roots of R. glutinosa". Rehmannia glutinosa is widely cultivated for its rhizomes which are used medicinally.