Excessive mucus, wheezing treated with TCM Cynanchum Rhizome

What is Bai Qian or Cynanchum Rhizome?
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.

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.