Bronchitis is inflammation of bronchial mucosa, congestion and edema, sticky secretion, irritating cough and spitting due to bacterial infection or allergies. To prevent bronchitis, the first thing is to prevent cold and keep warm, avoid colds and reduce bacterial infection. You can take ambroxol hydrochloride and other drugs to eliminate phlegm and relieve cough, and you can also use cephalosporins to diminish inflammation and avoid contact with allergic substances.