What Is Bronchitis?

Bronchitis (pronounced: brong-kye-tis) is an inflammation of the lining of the bronchial tubes, the airways that connect the trachea (windpipe) to the lungs. This delicate, mucus-producing lining covers and protects the respiratory system, the organs and tissues involved in breathing.

When a person has bronchitis, it may be harder for air to pass in and out of the lungs, the tissues become irritated, and more mucus is produced. The most common symptom of bronchitis is a cough.

When you breathe in (inhale), small, bristly hairs near the openings of your nostrils filter out dust, pollen, and other airborne particles. Bits that slip through become attached to the mucus membrane, which has tiny, hair-like structures called cilia on its surface. But sometimes germs get through the cilia and other defense systems in the respiratory tract and can cause illness.

Bronchitis can be acute or chronic. An acute medical condition comes on quickly and can cause severe symptoms, but it lasts only a short time (no longer than a few weeks). Acute bronchitis is most often caused by one of a number of viruses that can infect the respiratory tract and attack the bronchial tubes. Infection by certain bacteria can also cause acute bronchitis. Most people have acute bronchitis at some point in their lives.

Chronic bronchitis, on the other hand, can be mild to severe and is longer lasting — from several months to years. With chronic bronchitis, the bronchial tubes continue to be inflamed (red and swollen), irritated, and produce excessive mucus over time. The most common cause of chronic bronchitis is smoking.

People who have chronic bronchitis are more susceptible to bacterial infections of the airway and lungs, like pneumonia. (In some people with chronic bronchitis, the airway becomes permanently infected with bacteria.) Pneumonia is more common among smokers and people who are exposed to secondhand smoke.

What Are the Signs and Symptoms?

Acute bronchitis often starts with a dry, annoying cough that is triggered by the inflammation of the lining of the bronchial tubes. Other symptoms may include:

• cough that may bring up thick white, yellow, or greenish mucus
• headache
• generally feeling ill
• chills
• fever (usually mild)
• shortness of breath
• soreness or a feeling of tightness in the chest
• wheezing (a whistling or hissing sound with breathing)

Chronic bronchitis is most common in smokers, although people who have repeated episodes of acute bronchitis sometimes develop the chronic condition. Except for chills and fever, someone with chronic bronchitis has a chronic productive cough and most of the symptoms of acute bronchitis, such as shortness of breath and chest tightness, on most days of the month, for months or years.

A person with chronic bronchitis often takes longer than usual to recover from colds and other common respiratory illnesses. Wheezing, shortness of breath, and cough may become a part of daily life. Breathing can become increasingly difficult.

In people with asthma, bouts of bronchitis may come on suddenly and trigger episodes in which they have chest tightness, shortness of breath, wheezing, and difficulty exhaling (breathing out). In a severe episode of asthmatic bronchitis, the airways can become so narrowed and clogged that breathing is very difficult.

What Causes Bronchitis?

Acute bronchitis is usually caused by viruses, and it may occur together with or following a cold or other respiratory infection. Germs such as viruses can be spread from person to person by coughing. They can also be spread if you touch your mouth, nose, or eyes after coming into contact with respiratory fluids from an infected person.

Smoking (even for a brief time) and being around tobacco smoke, chemical fumes, and other air pollutants for long periods of time puts a person at risk for developing chronic bronchitis.

Some people who seem to have repeated bouts of bronchitis — with coughing, wheezing, and shortness of breath — may actually have asthma.

What Do Doctors Do?

If a doctor thinks you may have bronchitis, he or she will examine you and listen to your chest with a stethoscope for signs of wheezing and congestion.

In addition to this physical exam, the doctor will ask you about any concerns and symptoms you have, your past health, your family's health, any medications you're taking, any allergies you may have, and other issues (including whether you smoke). This is called the medical history. Your doctor may order a chest X-ray to rule out a condition like pneumonia, and may sometimes order a breathing test (called spirometry) to rule out asthma.

Because acute bronchitis is most often caused by a virus, the doctor may not prescribe an antibiotic (antibiotics only work against bacteria, not viruses).

The doctor will recommend that you drink lots of fluids, get plenty of rest, and may suggest using an over-the-counter or prescription cough medicine to relieve your symptoms as you recover.

In some cases, the doctor may prescribe a bronchodilator (pronounced: brong-ko-dy-lay-ter) or other medication typically used to treat asthma. These medications are often given through inhalers or nebulizer machines and help to relax and open the bronchial tubes and clear mucus so it's easier to breathe.

If you have chronic bronchitis, the goal is to reduce your exposure to whatever is irritating your bronchial tubes. For people who smoke, that means quitting!

If you have bronchitis and don't smoke, try to avoid exposure to secondhand smoke.

Smoking and Bronchitis

Tobacco smoke is the cause of more than 80% of all cases of chronic bronchitis. People who smoke also have a much harder time recovering from acute bronchitis and other respiratory infections.

Smoking causes lung damage in many ways. For example, it can cause temporary paralysis of the cilia and, over time, can kill the ciliated cells in the lining of the airways completely. Eventually, the airway lining stops clearing smoking-related debris, irritants, and excess mucus from the lungs altogether. When this happens, a smoker's lungs become even more vulnerable to infection.

Over time, harmful substances in tobacco smoke permanently damage the airways, increasing the risk for emphysema, cancer, and other serious lung diseases. Smoking also causes the mucus-producing glands to enlarge and make more mucus. Along with the toxic particles and chemicals in smoke, this causes a smoker to have a chronic cough.

Prevention

What's the best way to avoid getting bronchitis? Washing your hands often helps to prevent the spread of many of the germs that cause the condition — especially during cold and flu season.

If you don't smoke, don't ever start smoking — and if you do smoke, try to quit or cut down. Try to avoid being around smokers because even secondhand smoke can make you more susceptible to viral infections and increase congestion in your airway. Also, be sure to get plenty of rest and eat right so that your body can fight off any illnesses that you come in contact with.

Reviewed by: Steven Dowshen, MD
Date reviewed: November 2010