Knotweed is the dried whole grass of Maozi grass, family Zweiwei. It is mainly distributed in Yunnan and Guizhou. Its main functional value is to move Qi and relieve pain, eliminate food and stomach, stop dysentery, strengthen the spleen and dampness, and disperse blood stasis. It is mainly used in digestive diseases, such as gastritis, duodenitis, gastrointestinal dysfunction, diarrhea, nausea, vomiting, abdominal pain caused by indigestion and other diseases. If the drug is taken and the effect is not good after three days to one week, it is recommended to consult with the gastroenterology department. It is forbidden to take it if you are allergic to this drug, and the side effects are not known.