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, also called a chest cold, usually improves within a week to 10 days without lasting effects, although the cough may linger 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:

• Cough
• Production of mucus (sputum), which can be clear, white, yellowish-gray or green in color — rarely, it may be streaked with blood
• Fatigue
• Shortness of breath
• Slight fever and chills
• Chest discomfort

If you have acute bronchitis, you might have cold symptoms, such as a mild headache or body aches. While these symptoms usually improve in about a week, you may have a nagging cough that lingers for several weeks.

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 cough or other symptoms worsen. At those times, you may have an acute infection on top of 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
• Produces blood
• 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 cigarette smoking. Air pollution and dust or toxic gases in the environment or workplace also can contribute to the condition.

Factors that increase your risk of bronchitis include:

• Cigarette smoke. People who smoke or who live with a smoker are at higher risk of both acute bronchitis and chronic bronchitis.
• Low resistance. This may result from another acute illness, such as a cold, or from a chronic condition that compromises your immune system. Older adults, infants and young children have greater vulnerability to infection.
• Exposure to irritants on the job. Your risk of developing bronchitis is greater if you work around certain lung irritants, such as grains or textiles, or are exposed to chemical fumes.
• Gastric reflux. Repeated bouts of severe heartburn can irritate your throat and make you more prone to developing bronchitis.

Although a single episode of bronchitis usually isn't cause for concern, it can lead to pneumonia in some people. Repeated bouts of bronchitis, however, may mean that you have chronic obstructive pulmonary disease (COPD).

To reduce your risk of bronchitis, follow these tips:

• Avoid cigarette smoke. Cigarette smoke increases your risk of chronic bronchitis.
• Get vaccinated. Many cases of acute bronchitis result from influenza, a virus. Getting a yearly flu vaccine can help protect you from getting the flu. You may also want to consider vaccination that protects against some types of pneumonia.
• Wash your hands. To reduce your risk of catching a viral infection, wash your hands frequently and get in the habit of using alcohol-based hand sanitizers.
• Wear a surgical mask. If you have COPD, you might consider wearing a face mask at work if you're exposed to dust or fumes, and when you're going to be among crowds, such as while traveling.

During the first few days of illness, it can be difficult to distinguish the signs and symptoms of bronchitis from those of a common cold. During the physical exam, your doctor will use a stethoscope to listen closely to your lungs as you breathe.

In some cases, your doctor may suggest the following tests:

• Chest X-ray. A chest X-ray can help determine if you have pneumonia or another condition that may explain your cough. This is especially important if you ever were or currently are a smoker.
• Sputum tests. Sputum is the mucus that you cough up from your lungs. It can be tested to see if you have illnesses that could be helped by antibiotics. Sputum can also be tested for signs of allergies.
• Pulmonary function test. During a pulmonary function test, you blow into a device called a spirometer, which measures how much air your lungs can hold and how quickly you can get air out of your lungs. This test checks for signs of asthma or emphysema.

Most cases of acute bronchitis get better without treatment, usually within a couple of weeks.

Medications

Because most cases of bronchitis are caused by viral infections, antibiotics aren't effective. However, if your doctor suspects that you have a bacterial infection, he or she may prescribe an antibiotic.

In some circumstances, your doctor may recommend other medications, including:

• Cough medicine. If your cough keeps you from sleeping, you might try cough suppressants at bedtime.
• Other medications. If you have allergies, asthma or chronic obstructive pulmonary disease (COPD), your doctor may recommend an inhaler and other medications to reduce inflammation and open narrowed passages in your lungs.

Therapies

If you have chronic bronchitis, you may benefit from pulmonary rehabilitation — a breathing exercise program in which a respiratory therapist teaches you how to breathe more easily and increase your ability to exercise.

To help you feel better, you may want to try the following self-care measures:

• Avoid lung irritants. Don't smoke. Wear a mask when the air is polluted or if you're exposed to irritants, such as paint or household cleaners with strong fumes.
• Use a humidifier. Warm, moist air helps relieve coughs and loosens mucus in your airways. But be sure to clean the humidifier according to the manufacturer's recommendations to avoid the growth of bacteria and fungi in the water container.
• Consider a face mask outside. If cold air aggravates your cough and causes shortness of breath, put on a cold-air face mask before you go outside.

You're likely to start by seeing your family doctor or a general practitioner. If you have chronic bronchitis, you may be referred to a doctor who specializes in lung diseases (pulmonologist).

What you can do

Before your appointment, you may want to write a list that answers the following questions:

• Have you recently had a cold or the flu?
• Have you ever had pneumonia?
• Do you have any other medical conditions?
• What drugs and supplements do you take regularly?
• Are you exposed to lung irritants at your job?
• Do you smoke or are you around tobacco smoke?

You might also want to bring a family member or friend to your appointment. Sometimes it can be difficult to remember all the information provided. Someone who accompanies you may remember something that you missed or forgot.

If you've ever seen another physician for your cough, let your present doctor know what tests were done, and if possible, bring the reports with you, including results of a chest X-ray, sputum culture and pulmonary function test.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

• When did your symptoms begin?
• Have your symptoms been continuous or occasional?
• Have you had bronchitis before? Has it ever lasted more than three weeks?
• In between bouts of bronchitis, have you noticed you are more short of breath than you were a year earlier?
• Do your symptoms affect your sleep or work?
• Do you smoke? If so, how much and for how long?
• Have you inhaled illicit drugs?
• Do you exercise? Can you climb one flight of stairs without difficulty? Can you walk as fast as you used to?
• Does anything improve or worsen your symptoms?
• Does cold air bother you?
• Do you notice that you wheeze sometimes?
• Have you received the annual flu shot?
• Have you ever been vaccinated against pneumonia? If so, when?