Final answer:
Bronchitis is an inflammation of the bronchi caused by a bacterium or virus, resulting in a dry, painful cough that becomes productive. Antibiotics are usually not effective in treating acute bronchitis, as it is primarily caused by viruses.
Step-by-step explanation:
Bronchitis is an inflammation of the bronchi, the air passages that conduct air into the lungs. It is usually caused by either a bacterium or a virus. Acute bronchitis, which is the type characterized by a dry, painful cough that becomes productive, is commonly caused by viral or bacterial infections. The inflammation of the bronchi leads to redness, swelling, and mucus production, resulting in a productive cough. Shortness of breath and wheezing are also common symptoms of acute bronchitis. Antibiotics are typically not effective in treating acute bronchitis, as it is primarily caused by viruses.