Erythrina Bark (hai tong pi)

What is erythrina bark? What is it used for?

Erythrina bark is derived from the erythrina tree, which is native to India and southern Asia. The outer bark of the tree is light brown or grey, and notoriously thorny (which is part of the reason the tree is also known as the "coral bean"). The bark is harvested from the tree during the late spring and early summer, then dried in the sun.

According to the principles of traditional Chinese medicine, erythrina bark has bitter, pungent and neutral properties, and is associated with the Liver, Spleen and Kidney meridians. It is used to help treat rheumatic conditions such as joint pain, spasms of the legs and lower back, and knee pain. It also helps to promote urination, and is sometimes employed to treat certain skin conditions. Erythrina bark is often used with other herbs that have similar functions, such as tetrandra, clematis root and kadsura stem.

How much erythrina bark should I take?

The typical dosage of erythrina bark is between 6 and 12 grams, boiled in water as a decoction. Larger amounts of powdered erythrina bark can be applied to the skin as part of a poultice.

What forms of erythrina bark are available?

Erythrina bark is available in a variety of forms. In addition to whole, dried slices, erythrina bark is available as a powder, extract or capsule.

What can happen if I take too much erythrina bark? Are there any interactions I should be aware of? What precautions should I take?

Erythrina bark has received a class 1 rating from the American Herbal Products Association, meaning that it can be safely consumed when used appropriately. As of this writing, there are no known drug interactions or adverse side-effects associated with erythrina bark. As always, make sure to consult with a licensed health care provider before taking erythrina bark or any other herbal remedy or dietary supplement.

References

• Atindehou KK, Kone M, Terreaux C, et al. Evaluation of the antimicrobial potential of medicinal plants from the Ivory Coast. Phytother Res August 2002;16(5):497-502.
• McGuffin M, Hobbs C, Upton R, et al. (eds.) American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, 1997, p. 49.
• Sato M, Tanaka H, Fujiwara S, et al. Antibacterial property of isoflavonoids isolated from erythrina variegata against cariogenic oral bacteria. Phytomedicine 2003;10(5):427-33.
• Tanaka H, Etoh H, Shimizu H, et al. Two new isoflavonoids from erythrina variegata. Planta Med August 2000;66(6):578-9.
• Tanaka H, Sato M, Fujiwara S, et al. Antibacterial activity of isoflavonoids isolated from erythrina variegata against methicillin-resistant staphylococcus aureus. Lett Appl Microbiol 2002;35(6):494-8.