Chinese Foxglove

Scientific Name(s): Rehmannia glutinosa (Gaertn.) Libosch. ex Fisch & C.A. Mey
Common Name(s): Chinese foxglove, Di-Huang, Gun-Ji-Whang, Juku-Jio, Jyuku-Jio, Kan-Jiou, Saeng-Ji-Whang, Sheng Di Huang, Sho-Jio, Shou-Jiou, Shoudihuang, Shu Di Huang, Sook-Ji-Whang, To-Byun, Xiandihuang

Medically reviewed by Drugs.com. Last updated on Feb 21, 2022.

Clinical Overview

Use

Rehmannia rhizome extracts have been used extensively in traditional Chinese medicine. Because the preparation is often used in combination with other agents, it is difficult to attribute any benefits to R. glutinosa. Efficacy of R. glutinosa acteoside in the management of primary chronic glomerulonephritis has been suggested; however, clinical trials are lacking to support any use.

Dosing

Clinical studies are lacking to inform dosage. Common nonprescription polyherbal products contain varying amounts of Rehmannia root extract.

Contraindications

Chronic liver disease and GI disorders, including diarrhea.

Pregnancy/Lactation

Avoid use. Rehmannia has traditionally been used as an emmenagogue.

Interactions

None well documented.

Adverse Reactions

Minor and transient adverse reactions have been reported and include GI reactions (eg, diarrhea, abdominal pain), edema, heart palpitations, fatigue, and vertigo.

Toxicology

No data.

Scientific Family

• Scrophulariaceae

Botany

R. glutinosa is a perennial herb that grows wild in northern and northeastern China, particularly in Hunan province. It grows to a height of 0.3 to 0.6 m and has large, sticky leaves and purple flowers. The seed is sown in the autumn and spring; the yellow-brown to blackish-brown root is harvested after the plant has flowered in autumn. The fresh and dried roots and rhizomes have a soft texture, with deep longitudinal wrinkles on the external surface and a darker central cortex.Chevalier 1996, WHO 2007

History

R. glutinosa has been considered a panacea in traditional Chinese medicine, primarily in combination with other herbs. Dried Rehmannia rhizome is reputed to "nourish the yin" and remove heat from the blood, and is used as a tonic for the liver.

Documented historical uses include treatment of anemia, cancer, constipation, diabetes, fatigue, bacterial and fungal infections, hypertension, insomnia, tinnitus, inflammatory conditions, burns, impotence, and osteoporosis.WHO 2007, Zhang 2008

Chemistry

The major chemical constituents of the herb are polysaccharides and iridoid monoterpenes (eg, catalpol, ajugol, aucubin, rehmanniosides, monomelittoside, melittoside, verbascoside, jionosides). Two acidic polysaccharides, rehmannans SA and SB, were isolated from the dried root of R. glutinosa of Chinese origin. These polysaccharides were composed of differing molar ratios of L-arabinose, D-galactose, L-rhamnose, and D-galacturonic acid. Additional polysaccharides have been isolated. Pharmacological activity of the plant species varies depending on processing (dried or steamed) and location of cultivation (eg, Japan vs China). Other sesquiterpenoids and furans have been isolated.Kitagawa 1991, Li 2005, Oshima 1993, Oshio 1982, Tomoda 1994, WHO 2007 The most recently identified constituents include 3 alkaloids, rehmanalkaloids A, B, and C.Li 2017

Uses and Pharmacology

Rehmannia is most commonly used in combination with other herbs. Existing clinical trials do not provi...