||Cynanchi stauntonii rhizoma (bai qian) is acrid, bitter, sweet, slightly warming, and enters the Lung channel. A primary characteristic is its ability to direct qi downward. Its efficacy is related to the often quoted adage that "When qi descends, phlegm and thin mucus will disperse by themselves, and the cough will naturally cease." Because of this ability, Cynanchi stauntonii Rhizoma (bai qian) is known as an outstanding herb for Lung patients. Whenever profuse phlegm obstructs the Lungs leading to symptoms of cough, sensations of fullness in the chest, and wheezing, irrespective of whether the condition is hot or cold, it can be used, if properly combined with other herbs. This may be one reason that it is sometimes regarded as a neutral herb. An interesting quality mentioned in various materia medica texts is the ability of this herb to address qi gathered in the throat with audible phlegm. For example, the New Edition of Mei's Collected Empiric Formulas recommends powdered Cynanchi stauntonii Rhizoma (bai qian), taken with wine, to treat chronic cough that prevents sleep, with the rattling sound of phlegm in the throat. The Tang Materia Medica notes that the herb "primarily treats ascending qi rushing up into the throat, threatening to stop breathing." And Zhang Shan-Lei observes that "The reason that Cynanchi stauntonii Rhizoma (bai qian) can alleviate coughing lies in its ability to calm rebellious qi and prevent turbid qi below the diaphragm from rising up and accosting the Lungs."* --Bensky - Chinese Herbal Medicine Materia Medica, 3rd ed.