Basics
Acute bronchitis is a short-term respiratory illness that usually lasts less than 15 days. With bronchitis, air passages in the lungs become irritated, swell, and produce mucus.
Acute bronchitis is one of the top 10 reasons people in the United States seek medical care. Bronchitis is diagnosed based upon physical signs and symptoms, and by ruling out more serious illnesses (such as pneumonia). Cough is the main symptom of bronchitis. Bronchitis may also be called a lower respiratory infection, or “chest cold.” It occurs most often during the winter months, and may follow a head cold, the flu, or another illness.
Causes
Acute bronchitis is usually caused by a viral infection Figure 01[
Table 4 ].About 90% of infectious bronchitis cases (bronchitis caused by a germ) are viral. Viruses may be spread in the air when someone coughs or sneezes and another person inhales the germs. A person may also be exposed to viruses by shaking hands with an infected person, or touching something contaminated by an infected person.
Bacteria, yeast, and fungi may also cause bronchitis. However, since a virus usually causes bronchitis, antibiotics often will not be helpful in treating the illness. This is because antibiotics are only effective against bacteria [
Table 4 ].
Figure 01. Normal Lungs
Bronchitis can occur due to exposure to chemicals or irritants that are inhaled. This is referred to as occupational or environmental bronchitis.
You can avoid some bronchitis-causing irritants by refraining from smoking tobacco or other substances. If you work around dust or fumes, read and know the safety precautions recommended in the Material Safety Data Sheet(s) of the products or substances.
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I'm Shereen A. Gharbia, PharmD. Welcome to PDR Health!





