Bronchitis is an inflammation of the lining of your bronchial tubes, which carry air to and from your lungs. People who have bronchitis often cough up thickened mucus, which can be discolored. Bronchitis may be either acute or chronic.
Often developing from a cold or other respiratory infection, acute bronchitis is very common. Chronic bronchitis, a more serious condition, is a constant irritation or inflammation of the lining of the bronchial tubes, often due to smoking.
Acute bronchitis usually improves within a few days without lasting effects, although you may continue to cough for weeks. However, if you have repeated bouts of bronchitis, you may have chronic bronchitis, which requires medical attention. Chronic bronchitis is one of the conditions included in chronic obstructive pulmonary disease (COPD).
For either acute bronchitis or chronic bronchitis, signs and symptoms may include:
Production of mucus (sputum), which can be clear, white, yellowish-gray or green in color — rarely, it may be streaked with blood
Shortness of breath
Slight fever and chills
If you have acute bronchitis, you may have a nagging cough that lingers for several weeks after the inflammation resolves. Chronic bronchitis is defined as a productive cough that lasts at least three months, with recurring bouts occurring for at least two consecutive years.
If you have chronic bronchitis, you’re likely to have periods when your signs and symptoms worsen. At those times, you may have acute bronchitis on top of your chronic bronchitis.
When to see a doctor
See your doctor if your cough:
Lasts more than three weeks
Prevents you from sleeping
Is accompanied by fever higher than 100.4 F (38 C)
Produces discolored mucus
Is associated with wheezing or shortness of breath
Acute bronchitis is usually caused by viruses, typically the same viruses that cause colds and flu (influenza). Antibiotics don’t kill viruses, so this type of medication isn’t useful in most cases of bronchitis.
The most common cause of chronic bronchitis is smoking cigarettes. Air pollution and dust or toxic gases in the environment or workplace also can contribute to the condition.