Bitter and cold, Polygoni cuspidati Rhizoma (hu zhang) enters the Liver, Gallbladder, and Lung channels. Records of its clinical use over the centuries depict a growing appreciation for its wide range of clinical actions, which can be summed up as follows: invigorates the blood, breaks up stasis, expels pathogenic wind, eliminates dampness, cools heat, and resolves toxicity. Most recently, its ability to transform phlegm and stop coughs has received significant attention.