Chaff flower plant, Huai Niu Xi (Chinese) - Achyranthes Bidentata (Amaranthaceae)

Medicinal Use of Chaff flower, Huai Niu Xi (Chinese) – Achyranthes Bidentata (Amaranthaceae)


Erect perennial herb growing to 3 ft (1 m). Has slender, rambling branches, elliptical leaves, and greenish-white flowers on terminal spikes.

Habitat & Cultivation

Chaff flower is found in China at the edge of forests, along streams, and amid bushes. Grown commercially in the eastern provinces, the root is unearthed in winter once the foliage has died back.

Part Used



Achyranthes species contain triterpenoid saponins and sterones.

History & Folklore

Chaff flower’s potent ability to bring on menstruation led the 13th-century Chinese gynecologist Chen Ziming to prohibit its use during pregnancy to avoid causing miscarriage.

Medicinal Actions & Uses

In traditional Chinese medicine, chaff flower is believed to invigorate blood flow. It is used to stimulate menstruation when a period is delayed or scanty. The herb is also prescribed to ease period pain. Chaff flower is used to relieve pain in the lower back, especially where the discomfort is attributable to kidney stones. The herb is also taken as a treatment for canker sores, toothache, bleeding gums, and nosebleeds.


Research suggests that chaff flower may lower blood pressure by reducing heart rate and dilating the peripheral arteries.

Related Species

A. aspera, found in tropical areas worldwide, is used in Ayurvedic medicine to treat chest conditions and a range of digestive problems.


Do not take chaff flower during pregnancy.