Ercha, also known as Haiercha, Wudie Ni, or Wuding Ni, is mentioned in the book "Yinshan Zhengyao". It is a dried paste made from the heartwood or peeled branches of the plant Acacia catechu (L.f.) Willd. It is obtained by cutting down the tree in winter or spring, removing the white sapwood, cutting the brown heartwood into pieces, boiling and concentrating it into a greenish liquid, and then drying it into the final product, Ercha paste.
[Processing Method] Take the raw herb and remove impurities. Crush or grind it into fine powder when ready to use.
[Appearance] It is rectangular or irregularly shaped, varying in size. The surface is blackish-brown or reddish-brown, smooth with a slight luster, and often with leaves on the bottom. It is hard, brittle, with an uneven fracture surface and fine pores. It becomes sticky when exposed to moisture. It has a slight odor, astringent and bitter taste, with a slightly sweet aftertaste.
[Quality Requirements] Moisture content should not exceed 17.0%. The total content of catechin (C18H14O6) and epicatechin (C15H14O6) should not be less than 21.0%.
[Processing Actions] Ercha has a bitter, astringent, and cooling nature. It enters the heart, lung, and spleen meridians. It has the functions of drying dampness and healing sores, stopping bleeding and relieving pain, and clearing heat and transforming phlegm. After being processed, it is used for long-lasting non-healing ulcers, oozing damp sores, gingivitis, mouth ulcers, hemoptysis, hematemesis, hematuria, bloody stools, uterine bleeding, bleeding from external wounds, hemorrhoids, abscesses, phlegm-heat cough. It is also used in treating eczema and ulcers as Er Qing San ("Clinical Application of Chinese Medicine"); treating gastric and duodenal ulcers as Cha Min San ("Jilin Chinese Medicine", 1983); and for gastrointestinal bleeding as Zhi Xue Fen ("Journal of New Medicine", 1978). It can be used together with calcined Longgu, Xiangpi, Xuejie, Baiji, etc., to treat external bleeding. Processing improves the cleanliness of the medicine.
