What is rehmannia? What is it used for?
Rehmannia is a perennial herb indigenous to China, Japan and Korea. It
grows to a height of approximately 18 inches, and contains alternating
leaves with reddish-violet flowers. The root tuber is used medicinally.
In traditional Chinese medicine, rehmannia is used as a diuretic and
to strengthen the kidney, liver and heart. Fresh and dried forms of rehmannia
tuber are used differently. Fresh root tuber is used on the liver and
kidney meridians for conditions such as irregular menstruation; lowered
immunity; insomnia; tinnitus; vertigo; impaired hearing; diabetes; and
frequent urination. Dried tuber is used mainly for fevers and fever-related
conditions; dry mouth; nosebleeds; internal bleeding; rheumatism; and
constipation.
How much rehmannia should I take?
As a decoction, many practitioners recommend taking between 9-15 grams
of rehmannia. It can also be taken as part of a rice wine.
What forms of rehmannia are available?
Whole rehmannia tuber is available in either fresh or dried forms. Rehmannia
powder is sold at some Asian markets and specialty stores.
What can happen if I take too much rehmannia?
Are there any interactions I should be aware of? What precautions should
I take?
As of this writing, there are no known adverse reactions or drug interactions
with rehmannia. Rehmannia is considered safe as long as it is taken within
recommended therapeutic doses.
References
- Bensky D, Gamble A. Chinese Herbal Medicine, Materia
Medica. Seattle, Washington: Eastland Press Incorporated,
1993.
- Kubo M, Asano T, Matsuda H, et al. Studies on rehmanniae
radix. III. The relation between changes of constituents and improvable
effects on hemorheology with the processing of roots of rehmannia
glutinosa. Yakugaku Zasshi February 1996;116:158-68.
- Powerful and Unusual Herbs from the Amazon and
China. The World Preservation Society, Inc., 1995.
- Taylor M. Chinese Patent Medicines: A Beginner's
Guide. 1998, p. 85.
- Yuan Y, Hou S, Lian T, et al. Studies of rehmannia
glutinosa Libosch f. hueichingensis as a blood tonic. Chung Kuo
Chung Yao Tsa Chih June 1992;17:366-8.