Causes
Asthma is
caused by inflammation in the airways. When an asthma attack occurs, the
muscles surrounding the airways become tight and the lining of the air
passages swell. This reduces the amount of air that can pass by, and can
lead to wheezing sounds.
Most people with asthma have wheezing attacks separated by
symptom-free periods. Some patients have long-term shortness of breath
with episodes of increased shortness of breath. In others, a cough may
be the main symptom. Asthma attacks can last minutes to days and can
become dangerous if the airflow becomes severely restricted.
In sensitive individuals, asthma symptoms can be triggered by
breathing in allergy-causing substances (called allergens or triggers).
Common asthma triggers include:
- Animals (pet hair or dander)
- Dust
- Changes in weather (most often cold weather)
- Chemicals in the air or in food
- Exercise
- Mold
- Pollen
- Respiratory infections, such as the common cold
- Strong emotions (stress)
- Tobacco smoke
Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) provoke asthma in some patients.
Many people with asthma have an individual or family history of allergies, such as hay fever (allergic rhinitis) or eczema. Others have no history of allergies.
Exams and Tests
Allergy
testing may be helpful in identifying allergens in people with
persistent asthma. Common allergens include pet dander, dust mites,
cockroach allergens, molds, and pollens. Common respiratory irritants
include tobacco smoke, pollution, and fumes from burning wood or gas.
The doctor will use a stethoscope to listen to the lungs.
Asthma-related sounds may be heard. However, lung sounds are usually
normal between asthma episodes.
Tests may include:
- Arterial blood gas
- Blood tests to measure eosinophil count (a type of white
blood cell) and IgE (a type of immune system protein called an
immunoglobulin)
-
Chest x-ray
- Peak flow measurements
Symptoms »
-
Cough with or without sputum (phlegm) production
- Pulling in of the skin between the ribs when breathing (>
- Shortness of breath that gets worse with exercise or activity
- Wheezing
- Comes in episodes
- May be worse at night or in early morning
- May go away on its own
- Gets better when using drugs that open the airways (bronchodilators)
- Gets worse when breathing in cold air
- >Gets worse with exercise
- Gets worse with heartburn (reflux)
- Usually begins suddenly
Emergency symptoms:
-
Bluish color to the lips and face
- Decreased level of alertness such as severe drowsiness or confusion, during an asthma attack
- Extreme difficulty breathing
-
Rapid pulse
- Severe anxiety due to shortness of breath
- Sweating
Additional symptoms that may be associated with this disease:
- Abnormal breathing pattern --breathing out takes more than twice as long as breathing in
- Breathing temporarily stops
-
Chest pain
-
Nasal flaring
- Tightness in the chest
Treatment »
The
goal of treatment is to avoid the substances that trigger your symptoms
and to control airway inflammation. You and your doctor should work
together as a team to develop and carry out a plan for eliminating
asthma triggers and monitoring symptoms.
There are two basic kinds of medication for the treatment of asthma:
- Long-acting medications to prevent attacks
- Quick-relief medications for use during attacks
Long-term control medications are used on a regular basis to prevent attacks, not to treat them. Such medicines include:
- Inhaled corticosteroids (such as Azmacort, Vanceril, AeroBid, Flovent) prevent inflammation
- Leukotriene inhibitors (such as Singulair and Accolate)
- Long-acting bronchodilators (such as Serevent) help open airways
- Omilizumab (Xolair), which blocks a pathway that the immune system uses to trigger asthma symptoms
- Cromolyn sodium (Intal) or nedocromil sodium (Tilade)
- Aminophylline or theophylline (not used as frequently as in the past)
- Sometimes a single medication that combines steroids and bronchodilators are used (Advair, Symbicort)
Quick relief, or rescue, medications are used to relieve symptoms during an attack. These include:
- Short-acting bronchodilators (inhalers), such as Proventil, Ventolin, Xopenex, and others
- Corticosteroids, such as methylprednisolone, may be given
directly into a vein (intravenously), during a severe attack, along with
other inhaled medications
People with mild asthma (infrequent attacks) may use quick relief
medication as needed. Those with persistent asthma should take control
medications on a regular basis to prevent symptoms. A severe asthma
attack requires a check up by a doctor and, possibly, a hospital stay,
oxygen, and medications through a vein (IV).
A peak flow meter is a simple device to measure how quickly you
can move air out of your lungs. It can help you see if an attack is
coming, sometimes even before any symptoms appear. Peak flow
measurements can help show when medication is needed, or other action
needs to be taken. Peak flow values of 50-80% of a specific person's
best results are a sign of a moderate asthma attack, while values below
50% are a sign of a severe attack.