Bronchitis is very common, almost everyone has had bronchitis, 1-2 times a year, in the case of cold, overwork, overtime, strain, mental stress, etc. can cause a decrease in the defense function of the whole body and the respiratory tract, which is the basis for the formation of bronchitis, its causes include: 1, pathogens invade into the trachea, bronchi, pathogens including viruses bacteria, mycoplasma, chlamydia, etc., can be in the The physical and chemical stimuli include physical factors such as cold air, dust, harmful fumes, and chemical factors including sulfur dioxide, chlorine, concentrated sulfuric acid, and other gases that can irritate and damage the airways after entering the airways and cause bronchitis. 3. Allergic factors such as pollen, fungal spores, and bacterial bodies and proteins that can Bronchitis occurs when allergic reactions are caused by migration in the airways, and this is how bronchitis forms. This has to have the basis of immune function decline, in the pathogens, physical and chemical factors, allergic factors stimulation caused by the trachea and bronchial mucosa congestion, edema and bronchitis.