The hazards of bronchitis are as follows: 1. lower lung function: after the onset of the disease, the secretion of glands in the tracheal mucosa increases, i.e., sputum increases, and the body needs to expel the sputum by coughing, which leads to a decline in lung function and accelerates the progress of the disease in the long term; 2. affect the quality of life: frequent coughing prevents patients from lying down or even sleeping normally; 3. easily complicate chronic obstructive pulmonary disease, emphysema, pulmonary heart disease, etc.; 4. prolonged illness easily leads to chronic bronchitis, which recurs with seasonal changes and is difficult to cure.