Bronchitis is inflammation of the bronchial tubes caused by viruses, bacteria, smoking, and other irritants. It can be acute, lasting a few weeks, or chronic, lasting over 3 months. Symptoms include cough, sputum production, wheezing, and shortness of breath. Treatment focuses on airway clearance using expectorants, bronchodilators, corticosteroids, and antibiotics for secondary infections. Smoking cessation, exercise, chest physiotherapy, and oxygen therapy can help manage chronic bronchitis. Nursing care emphasizes improving breathing, clearing secretions, preventing infections, and enhancing coping skills.