Also known as Cynanchum Rhizome and Willowleaf Swallowwort Rhizome, it refers to the root of cynanchum stauntonii (Decne.) or cynanchum glaucescens (Decne.), which grows in a few of provinces in China like Jiangsu, Anhui, Zhejiang, and Guizhou, etc.

Dried roots of cynanchum stauntonii twist into lump. The single one is tubelike, tall and slender with nodules, slightly curved, 4 to 15cm long, 1.5 to 5mm in diameter, light yellow to yellowish-brown skin, small vertical wrinkles, expanded nodules, branching with dense fibril, and often with remnant grayish-green or purple-brown aerial stem of plant on top. It is crisp and easy to break, round cross section, and hollow or marrow with membrane in the middle.

Dried root of Cynanchum glaucescens is similar to that of cynanchum stauntonii. But it features opposite buds on nodules of rhizome and overground stem. The root is long the thick, about 5 to 20cm, 0.5 to 1mm in diameter, light gray yellow skin. And it is with faint odor and slightly sweet in taste. The preferred medicinal herb is bigger build, longer fibril, and without dirt and impurities.

Excessive mucus in throat is one of common symptoms of inflammatory airway, which occurs more commonly in children and the elderly. Most coughing always accompanies with this substance. So to speak, where there is excess mucus production, there is coughing. This is simply because coughing is a defensive reaction of the human body, which helps get them out of throat in case it induces more severe diseases like Pneumonia due to obstruction in respiratory tract. However, when body fails to get rid of them thoroughly, it should seek outside help immediately. When it comes to Chinese herbs for excessive phlegm, Bai Qian is one of not bad choices.

Cynanchum Rhizome

PROPERTY AND INDICATIONS
From the perspective of Traditional Chinese Medicine (TCM), it is pungent, bitter, and slight warm in nature and covers lung meridian. Main functions are to descend reversed Qi, transform phlegm, and relieve a cough. Main usage and indications are coughing up excessive mucus and wheezing, regardless it is of cold or hot nature, exopathic cause or internal injury, and newly acquired or chronic type. Regular dosage is 3 to 19 grams in decoction.

RELATED NATURAL REMEDIES FOR EXCESSIVE MUCUS IN THROAT 
(1). Recorded in Shi Ji Yan Fang (Collection of Effective Recipes), its powder mixed with warm wine is used to treat gurgling throat and insomnia due to chronic phlegm;

(2). According to Jin Xiao Fang (Recent Effective Recipes), there is a recipe that is exclusively used for chronic coughing up blood in mucus. Other individual herbs are Sang Bai Pi (Mulberry Root Bark), Jie Geng (Balloon Flower Rhizome), and Gan Cao (Licorice Root);

(3). Di Gu Pi Tang, from Sheng Ji Zong Lu (Complete Record of Holy Benevolence), is mainly for excess heat in lung, full chest due to asthma, rapid breathing, and lying in chair or bed caused by excessive mucus in throat and lung. The formula includes Di Gu Pi (Wolfberry Root Cortex), Bai Qian (Cynanchum Rhizome), Shi Gao (Gypsum), Xing Ren (Apricot Seed), and Sang Bai Pi (Mulberry Root Bark).