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 may have it for the rest of your life.
You may start coughing or wheezing when you breathe in irritants or something you are allergic to. Cold air, chemicals, perfume and smoke are examples of irritants. Examples of things you might be allergic to, called allergens, are dust, pollen, molds and animal dander. A viral respiratory infection might also bring on an asthma attack.
Some people have coughing or wheezing only during or after physical activity. 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 prompt treatment for asthma attacks and to learn to manage your asthma so you can live a healthy, active life.v
About 12 million Americans have asthma, and the number of people who have asthma is increasing worldwide.
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 make more mucus. The tiny muscles in the walls of the airways 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.
Some of the factors that may increase the risk of developing asthma are:
- Low birth weight
- Having one or both parents with asthma
- Exposure to secondhand smoke or a lot of environmental pollutants (for example, in a large city)
- On-the-job exposure to chemicals used in the manufacturing industry, farming and hairdressing
What are the symptoms?
Symptoms of asthma are:
- Wheezing (a high-pitched whistling sound when you breathe in or out)
- Shortness of breath
- Chest tightness
How is it diagnosed?
Your health care provider will ask about your history of breathing problems. You will have a physical exam. You may have one or more breathing tests. You may be tested before and after taking medicine to see how your symptoms respond to medicine.
A single attack of wheezing does not mean you have asthma. Some infections and chemicals can cause wheezing that lasts for a short time and then does not happen again. Before deciding whether you have asthma, your health care provider may want to see if you have another attack of wheezing.
How is it treated?
The goal of treatment is to allow you to live a normal, active life. Treatment will probably include prescribed medicines and the removal of obvious allergy-causing substances or irritants from your home.
Two types of medicines are used to control asthma:
- Quick-acting medicines called bronchodilators
- Preventive medicines
Quick-acting bronchodilators (rescue medicines):
Albuterol is the generic name of the most widely used quick-acting bronchodilator. Bronchodilators relax the muscles in the airways. When the muscles are relaxed, the airways become larger, so there is more space for air to move in and out. You take this medicine by inhaling it when you first begin to have symptoms. You breathe it into your lungs as you spray it into your mouth. If you have asthma attacks often, you should always carry a bronchodilator with you to use when you begin to wheeze. If you have exercise-induced asthma, you should use the medicine before exercise to prevent wheezing.
Several types of medicines help control asthma. These medicines are now considered the best and safest way to control asthma. They help reduce the inflammation in your airways. They do not stop attacks of wheezing once the wheezing starts. You must use a quick-acting bronchodilator (rescue medicine), such as albuterol, when you are wheezing.
The goals of preventive medicines are to:
- Control asthma attacks
- Control chronic asthma symptoms, such as shortness of breath
- Allow you to live a fully active life, including sports activities
The medicines used most often for prevention are:
- A long-acting, inhaled bronchodilator called salmeterol (Serevent) used two times a day
- Inhaled steroids, such as Azmacort and Flovent, used one to four times a day
- Zafirlukast (Accolate), zileuton (Zyflo), or montelukast (Singulair) pills taken daily
Other preventive medicines include:
- Theophylline, a pill often taken at bedtime to control nighttime wheezing
- Cromolyn or nedocromil, inhaled three to four times a day