Bronchitis is the sudden development of inflammation in bronchial tubes—the major airways into your lungs. It usually happens because of a virus or breathing in something that irritates the lungs such as tobacco smoke, fumes, dust and air pollution.
- Bronchitis is temporary and usually does not cause any permanent breathing difficulties.
- The infection usually lasts for a week to 10 days, but the cough can continue for several weeks.
- Bronchitis usually gets better on its own without the need for medical treatment.
- It is different from chronic bronchitis, a chronic disease that is part of COPD.
- Young children, the elderly and people with major health conditions are the most at risk.
How Acute Bronchitis Affects Your Body
In bronchitis, cells that line the bronchi become infected. The infection usually starts in the nose or throat and travels to the bronchial tubes. When the body tries to fight the infection, it causes the bronchial tubes to swell. This causes you to cough. Sometimes it is a dry cough, but often you will cough up mucus (sputum). The swelling also narrows your airways, allowing less air to pass through, which can cause wheezing, chest tightness and shortness of breath. With time, the immune system can fight off the infection and your airways return to normal.
What Causes Bronchitis?
Acute bronchitis is usually caused by a virus, such as a cold or the flu, and occasionally by bacterial infection.
You are more vulnerable to developing bronchitis if:
- You have close contact with someone who has a cold or acute bronchitis
- You have not been immunized against the flu
- You are exposed to lung irritants like tobacco smoke, fumes, dust and air pollution
Reviewed and approved by the American Lung Association Scientific and Medical Editorial Review Panel.
Page last updated: January 25, 2021