October 15, 2014


What is asthma?

Asthma is a  disease of the lungs in which the airways are inflamed. Exposure to allergens and irritants cause asthma flare-ups. Several things happen to the airways when a person is exposed to allergen or irritant triggers:

  • The lining of the airways becomes swollen and inflamed.

  • The muscles that surround the airways tighten.

  • More mucus is produces leading to mucus plugs in the airways

The airways then narrow, making it difficult for air to go in and out of your lungs.

What are the symptoms of asthma?

Asthma may resemble other respiratory problems, such as emphysema, bronchitis, and lower respiratory infections. Many people with the disease do not know they have it. Sometimes, the only symptom is a chronic cough, especially at night, or coughing or wheezing that occurs only with exercise. The most common symptoms are:

  • Wheezing, or whistling sound when breathing

  • Frequent cough

  • Shortness of breath

  • Chest tightness

What causes asthma?

The exact cause of asthma is not completely known. It is believed to be partially inherited, but it also involves many other factors. After a person is exposed to a certain trigger, the body releases substances that can cause inflammation in the airways. The body also releases substances that can cause the muscles of the airways to tighten or become smaller. There is also an increase in mucus production that may clog the airways.

Some people have exercise-induced bronchoconstriction (a narrowing of airways that occurs with exercise). Symptoms occur during, or shortly after, exercise. In some people, stress or strong emotions can trigger an asthma attack. Each person has different triggers that cause symptoms. Discuss your triggers with your health care provider.

The changes that occur in asthma are believed to happen in two phases, one that happens right away and a second response 4 to 8 hours later. They both cause swelling and narrowing of the airways. 

What are the risk factors for asthma?

Although anyone can develop asthma , it most commonly occurs in the following people:

  • Children and adolescents ages 5 to 17

  • People living in cities

Other factors include the following:

  • Family history of asthma

  • Personal history of allergies

  • Exposure to secondhand tobacco smoke

What happens during an asthma attack or exacerbation?

People with asthma have acute episodes when the air passages in their lungs become narrower, and breathing becomes more difficult.

  • Breathing becomes harder and may become painful.

  • Talking and sleeping may be difficult.

  • Coughing and mucus production may increase.

  • Wheezing may occur.

How is asthma diagnosed?

Medical history and physical exam bare used to diagnosed asthma. The following test may also be done:

  • Spirometry. A spirometer is a device that assesses lung function. The test is done by blowing as hard as possible into a tube connected to a spirometer. It measures the amount and speed of air breathed out. Spirometry is done to:

    • Monitor a lung disease

    • Monitor the effectiveness of treatment

    • Determine the severity of a lung disease

  • Peak flow monitoring (PFM). This measures the fastest speed in which a person can blow air out of the lungs. A person takes a deep breath in and then blows as hard and fast as possible into a mouthpiece. The changes that occur with asthma slow the speed of air leaving the lungs and can be measured by a PFM. This measurement is very important in evaluating how well asthma is being controlled.

  • Chest X-rays

  • Blood tests. Tests to measure the amount of carbon dioxide and oxygen in the blood.

  • Allergy tests

What are asthma triggers?

According to the CDC, the American Academy of Allergy, Asthma, and Immunology, and other organizations, triggers for asthma include the following:


Respiratory infections

  • Pollen

  • Mold

  • Animal protein (dander, urine, oil from skin)

  • House dust or dust mites

  • Cockroach droppings

  • Certain foods

Infections can cause irritation of the:

  • Nose

  • Throat

  • Lungs

  • Sinuses



  • Strong odors and sprays, such as perfumes, household cleaners, cooking fumes, paints, and varnishes

  • Chemicals, such as coal, chalk dust, or talcum powder

  • Air pollutants, such as chemicals in the air and ozone

  • Changing weather conditions, including temperature, barometric pressure, humidity, and strong winds

  • Chemical exposure on the job, such as dust, gases, or fumes.

  • Aspirin

  • Other nonsteroidal anti-inflammatory medications (NSAIDs), such as ibuprofen, indomethacin, naproxen

  • Sulfites used as preservatives in food and beverage


Gastroesophageal reflux (GERD)

Strenuous physical exercise such as long-distance running.

Common in people with asthma. Symptoms may include heartburn, belching, or spitting up in infants.


Anxiety and stress

Tobacco smoke from inhaling or from secondhand smoke.

Wood smoke from wood-burning heating stoves and fireplaces

Can cause fatigue, which may affect the immune system and increase asthma symptoms or cause an attack.


May 28, 2014

Reviewed By:  

Akin, Louise, RN, Holloway, Beth, RN, M.Ed.