Prepared Rehmannia root, or Shu di huang, is extracted from a plant native to northeast China. Due to its many benefits to the body, Shu di huang is a plant that mitigates the effects of fatigue while strengthening the body.

In TCM, Shu di huang is classified among the plants that tonify the Blood. It is also known to nourish the Liver and Kidney Yin. Thus, in addition to allowing a revival of tone, it preserves the well-being of the body.