The symptoms of bronchitis are: 1. cough, cough is one of the first symptoms of lower respiratory tract infection bronchitis, followed by coughing, dry cough or a small amount of mucus sputum, after 2-3 days coughing intensifies, sputum volume increases or mucopurulent sputum, coughing is frequent and can be accompanied by a burning sensation behind the sternum. 2. coughing sputum, mostly white mucus sputum or white foamy sputum, more sputum in the morning and evening, co-infected Sputum volume increases and mucopurulent sputum appears. 3. wheezing symptoms, some patients may develop bronchial asthma and spasms. 4. systemic symptoms, such as fever and headache, which last for 3-5 days and can be slightly relieved.