Bronchitis is inflammation of the bronchial tubes caused by viruses, bacteria, or other irritants. It can be acute, lasting a few weeks, or chronic, characterized by a long-term productive cough. Symptoms include cough, mucus production, shortness of breath, wheezing, and chest discomfort. Treatment depends on the cause but may include antibiotics, cough medicine, bronchodilators, mucolytics, or steroids. Lifestyle changes like quitting smoking and avoiding irritants can help prevention.