Bronchitis is an inflammation of the main air passages to the lungs. Bronchitis may be short-lived (acute) or chronic, meaning that it lasts a long time and often recurs.

See also: Chronic obstructive pulmonary disease (COPD)

Acute bronchitis generally follows a viral respiratory infection. At first, it affects your nose, sinuses, and throat and then spreads to the lungs. Sometimes, you may get another (secondary) bacterial infection in the airways.This means that bacteria infect the airways, in addition to the virus.

People at risk for acute bronchitis include:

• Elderly, infants, and young children
• Persons with heart or lung disease
• Smokers

Chronic bronchitis is a long-term condition. People have a cough that produces excessive mucus. To be diagnosed with chronic bronchitis, you must have a cough with mucus most days of the month for at least 3 months.

Chronic bronchitis is also known as chronic obstructive pulmonary disease, or COPD for short. (Emphysema is another type of COPD.) As the condition gets worse, you become increasingly short of breath, have difficulty walking or exerting yourself physically, and may need supplemental oxygen on a regular basis.

Cigarette smoke, including long-term exposure to second-hand smoke, is the main cause of chronic bronchitis. The severity of the disease often relates to how much you smoked or how long you were exposed to the smoke.

The following things can make bronchitis worse:

• Air pollution
• Allergies
• Certain occupations (such as coal mining, textile manufacturing, or grain handling)
• Infections

The symptoms of either type of bronchitis may include:

• Chest discomfort
• Cough that produces mucus; if it's yellow-green, you are more likely to have a bacterial infection
• Fatigue
• Fever -- usually low
• Shortness of breath worsened by exertion or mild activity
• Wheezing

Even after acute bronchitis has cleared, you may have a dry, nagging cough that lingers for several weeks.

Additional symptoms of chronic bronchitis include:

• Ankle, feet, and leg swelling
• Blue-colored lips from low levels of oxygen
• Frequent respiratory infections (such as colds or the flu)

The health care provider will listen to your lungs with a stethoscope. Abnormal sounds in the lungs called rales or other abnormal breathing sounds may be heard.

Tests may include:

• Chest x-ray
• Lung function tests provide information that is useful for diagnosis and your outlook.
• Pulse oximetry helps determine the amount of oxygen in your blood. This quick and painless test uses a device that is placed onto the end of your finger. Arterial blood gas is a more exact measurement of oxygen and carbon dioxide levels, but it requires a needle stick and is more painful.
• Sputum samples may be taken to check for signs of inflammation or bacterial infection.

You DO NOT need antibiotics for acute bronchitis caused by a virus. The infection will generally go away on its own within 1 week. Take the following steps for some relief:

• Do not smoke
• Drink plenty of fluids
• Rest
• Take aspirin or acetaminophen (Tylenol) if you have a fever. DO NOT give aspirin to children
• Use a humidifier or steam in the bathroom

If your symptoms do not improve, your doctor may prescribe an inhaler to open your airways. If your doctor thinks that you have a secondary bacterial infection, antibiotics will be prescribed.

For chronic bronchitis, the most important step you can take is to QUIT smoking. If caught early enough, you can reverse the damage to your lungs. Other important steps include:

• Limit your exposure to pollutants and other lung irritants.
• Get a flu vaccine each year and a pneumococcal vaccine as directed by your doctor.
• Attend a respiratory training program that includes physical activity and breathing exercises. Your doctor can recommend a medically appropriate and well-supervised program. If it is early in the disease process, you can likely exercise on your own. Talk to your doctor about safety.

Your doctor will usually prescribe inhaled medicines for chronic bronchitis. These drugs, which include bronchodilators like albuterol and ipratropium, open your airways and help clear mucus. A bronchodilator taken by mouth (theophylline) and steroids (either inhaled or by mouth) are often necessary as well. If you have an active infection, your doctor will put you on antibiotics. You may also need antibiotics to prevent infection.

If you have low oxygen levels, home oxygen will be used.

For acute bronchitis, symptoms usually go away within 7 to 10 days if you do not have an underlying lung disorder. However, a dry, hacking cough can linger for a number of months.

The chance for recovery is poor for persons with advanced chronic bronchitis. Early recognition and treatment, combined with smoking cessation, significantly improve the chance of a good outcome.

Pneumonia can develop from either acute or chronic bronchitis. If you have chronic bronchitis, you are more likely to develop recurrent respiratory infections. You may also develop:

• Emphysema
• Right-sided heart failure or cor pulmonale
• Pulmonary hypertension

Call your doctor if:

• You have a cough most days or you have a cough that returns frequently
• You are coughing up blood
• You have a high fever or shaking chills
• You have a low-grade fever for 3 or more days
• You have thick, greenish mucus, especially if it has a bad smell
• You feel short of breath or have chest pain
• You have an underlying chronic illness, like heart or lung disease

• DO NOT smoke.
• Get a yearly flu vaccine and a pneumococcal vaccine as directed by your doctor.
• Reduce your exposure to air pollution.
• Wash your hands (and your children's hands) frequently to avoid spreading viruses and other infections.

Gwaltney JM. Acute bronchitis. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 6th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2005:chap 58.

GOLD Scientific Committee. Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease: GOLD Executive Summary updated 2006.