What is asthma?

Asthma is a lung condition that causes wheezing, coughing, and shortness of breath. It is caused by inflammation (swelling) of the lining of the airways in your lungs. Asthma is a chronic condition, which means you will probably have it the rest of your life.

You may start coughing or wheezing when you breathe in irritants or something you are allergic to. Cold air, viruses, and tobacco smoke are possible irritants. Examples of things you might be allergic to are dust, pollen, molds, and animal dander. Some people have coughing or wheezing only during exercise. This is called exercise-induced asthma.

Asthma may be mild, moderate, or severe. An asthma attack may last a few minutes or for days. Attacks can happen anywhere and at any time. Severe asthma attacks can be fatal. It is very important to get treatment for asthma so you can live a healthy, active life.

How does it occur?

If you have asthma, the airways in your lungs are always somewhat inflamed, even when you do not have any symptoms. When your airways are exposed to irritants or allergens, the airways become more swollen and begin to make excess mucus. The tiny muscles in the walls of the airways begin to contract. These reactions cause the airway openings to become smaller, making it harder for air to move in and out. Wheezing is the sound of air moving through the narrowed air passages. The extra mucus in the airways causes coughing.

About 12 million Americans have asthma, and the number of people who have asthma is increasing worldwide.

What are the symptoms?

Symptoms of asthma include wheezing, coughing, shortness of breath, and chest tightness.

How is it diagnosed?

Your health care provider will ask about your history of breathing problems and will do a physical exam. You may have one or more breathing tests. You may be tested before and after taking medication to measure your response to medication.

A single attack of wheezing does not necessarily mean that you have asthma. Certain infections and some chemicals can cause wheezing that lasts for a short time and then does not occur again. Before deciding whether you have asthma, your provider may want to see if you have another attack of wheezing.

How is it treated?

The goal of asthma therapy is for you to live a normal, active life. Your treatment will probably include prescribed medication and the removal of any obvious allergy-causing substances or irritants from your environment.

Two main types of medications are used to control asthma: bronchodilators and anti-inflammatory drugs.

If you have mild or exercise-induced asthma, your health care provider may prescribe a short-acting bronchodilator to prevent and treat asthma attacks. ('Short-acting' means that the medicine works for just a short time.) Bronchodilators relax the muscles in the airways. When the muscles are relaxed, the airways become larger and allow more space for air to move in and out. These drugs are most often prescribed as inhalers. Inhalers are medicines that you breathe into your lungs as you spray them into your mouth.

Salmeterol is a new, long-acting, inhaled bronchodilator. It can be taken every day to help prevent wheezing. It should not be used to treat sudden attacks of wheezing because it works too slowly. If you are using salmeterol, you should always carry a short-acting bronchodilator with you to use when you have an attack.

Some bronchodilators are tablets or capsules that you swallow. Theophylline, for example, may be taken in capsule form. It is used less often these days because the newer inhalers work faster and have less serious side effects. Some people, however, find theophylline more effective. It is particularly useful if you have nighttime asthma.

Especially for more severe asthma, your health care provider may prescribe anti-inflammatory medicines to be taken every day. Types of anti-inflammatory drugs include cromolyn sodium inhalers, steroid inhalers and tablets, and nedocromil inhalers. These medicines help reduce the inflammation in your airways. They do not stop attacks of wheezing once the wheezing starts. You must use a short-acting bronchodilator when you are wheezing.

Make sure you know how to use your inhaler correctly. Read the directions that come with your inhaler. Most inhalers work best if you hold them 1 to 2 inches in front of your mouth when you spray. If you close your mouth around the inhaler, less of the spray of medicine will reach your lungs. If it is hard for you to hold the inhaler in the right position, ask your health care provider for a spacer tube. You can put one end of the spacer in your mouth and attach the inhaler to the other end. This allows you to breathe in slowly and fully and to inhale more of the asthma medicine.

Learn how to tell when your inhaler canister is empty. To see if it is getting empty, float the canister in a bowl of water. A full canister sinks. An empty canister floats. Ask your health care provider for a diagram that shows how to test your canister.

Your breathing ability can change from day to day. For example, illness or seasonal allergies may make your airways more inflamed than usual. Your provider may prescribe a peak flow meter for you to use at home to check your breathing ability. You can then know when you might need to increase your dosage of medicine to prevent severe attacks of wheezing.

Ways to remove substances in your home that may cause wheezing are described below.

How can I take care of myself?

Depending on your specific allergies, these guidelines may help keep allergens and irritants out of your home:

• Cover mattresses, box springs, and pillows with zippered plastic covers.

• Wash bedding in hot water once a week.

• Wash and thoroughly dry pillows once a month.

• Avoid using a vaporizer or humidifier unless it is thoroughly cleaned regularly to remove mold.

• It is best to not have pets. If you do have a pet, bathe your pet weekly, vacuum frequently and thoroughly, and use a HEPA (high efficiency particulate arresting) air filter.

• Stay indoors when the humidity or pollen count is high.

• Use air conditioning instead of open windows to cool your home.

• Do not use attic fans.

• Avoid cigarette smoke.

• Avoid vapors from harsh chemicals, such as bleach.

You should also:

• Take your medicines exactly as prescribed.

• Get an influenza vaccine every October.

Tell your health care provider if your medication is not preventing coughing, wheezing, or shortness of breath, or if you are developing signs of a cold or other respiratory infection.

If you need to use your bronchodilator inhaler more often than every 4 hours, tell your provider.

How long will the effects of asthma last?

Asthma is a chronic condition, even though you might not have any symptoms for decades. Asthma is more common in children than adults. People who had asthma as children often have no symptoms once they become adults, but the symptoms may come back later in life. Asthma that develops for the first time in mid- or late life usually continues to be a problem for the rest of your life.