Please note that you should never self-prescribe TCM ingredients. A TCM ingredient is almost never eaten on its own but as part of a formula containing several ingredients that act together. Please consult a professional TCM practitioner, they will be best able to guide you.
Preparation: The roots are steamed and dried in the sun 9 times before being dried for a final time.
Dosage: 9 - 30 grams
Main actions according to TCM*: Tonifies the Blood. Tonifies the Yin of the Kidneys.
Contraindications*: This herb should be used with caution by those with weak digestion and Spleen Qi. It should be avoided by those with Stagnation of Qi or Phlegm.
Common TCM formulas in which prepared rehmannia are used*:
In Traditional Chinese Medicine (TCM), prepared rehmannia are plants that belong to the 'Tonic herbs for Blood Deficiency' category. Tonic herbs are used for patterns of Deficiency, when one lacks one of the 'Four Treasures' (Qi, Blood, Yin and Yang). Blood tonics tend to be bitter-sweet with either a Warm or neutral nature. Because the Liver stores Blood, all Blood tonics enter that Organ meridian.
As suggested by its category prepared rehmannia are plants that are Warm in nature. This means that prepared rehmannia tend to help people who have too much "cold" in their body, although with less effect than a plant that would be Hot in nature. Balance between Yin and Yang is a key health concept in TCM. Those who have too much cold in their body are said to either have a Yin excess (because Yin is Cold in nature) or a Yang deficiency (Yang is Hot in Nature). Depending on your condition prepared rehmannia can help restore a harmonious balance between Yin and Yang.
Prepared rehmannia also taste Sweet. The so-called "five elements" theory in Chinese Medicine states that the taste of TCM ingredients is a key determinant of their action in the body. Sweet ingredients like prepared rehmannia tend to slow down acute reactions and detoxify the body. They also have a tonic effect because they replenish Qi and Blood.
The tastes of ingredients in TCM also determine what organs and meridians they target. As such prepared rehmannia are thought to target the Kidney and the Liver. According to TCM, the Kidneys do not only regulate the urinary system but also play a key role in the reproductive system and the growth and aging process of the body. The Liver on the other hand is often referred as the body's "general" because it is in charge of regulating the movements of Qi and body fluids. It also takes a leading role in balancing our emotions.
Bushen Qiangdu Recipe (consisting of prepared rehmannia root) showed significant effect in treatment of ankylosing spondylitis.1
Dandi Tablet (consisting of prepared Rehmannia Root) has the effect of elevating levels of estrogen and improving blood lipid metabolism, therefore shows a coronary heart disease preventive effect in women of postmenopausal stage.2
Runmushu Oral Liquid (consisting of prepared rehmannia root) with artificial-tears can alleviate the eye symptoms, promote the secretion of tears in treating postmenopausal women xerophthalmia. 3
1. Wang H, Yan XP, Kong WP. (2011). Effect of bushen qiangdu recipe on osteoporosis and bone loss of patients with ankylosing spondylitis. Zhongguo Zhong Xi Yi Jie He Za Zhi. , 31(4):471-5.
2. Liang R, Chen MR, Xu X. (2003). Effect of dandi tablet on blood lipids and sex hormones in women of postmenopausal stage. Zhongguo Zhong Xi Yi Jie He Za Zhi. , 23(8):593-5.
3. Wei D, Li YH, Zhou WY. (2009). Observation on therapeutic effect of runmushu oral liquid in treating xerophthalmia in postmenopausal women. Zhongguo Zhong Xi Yi Jie He Za Zhi. , 29(7):646-9.