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Asthma: Identifying Your Triggers

What is an Actionset?

Asthma is a long-lasting (chronic) disease of the respiratory system. It causes inflammationClick here to see an illustration. in tubes that carry air to the lungs (bronchial tubes). The inflammation makes your bronchial tubes likely to overreact to certain triggers. An overreaction can lead to decreased lung function, sudden difficulty breathing, and other symptoms of an asthma attack.

If you avoid triggers, you can:

  • Prevent some asthma attacks.
  • Reduce the frequency and severity of some attacks.

You may not be able to avoid or even want to avoid all your asthma triggers. But you can identify many things that trigger your symptoms by:

  • Monitoring your lung function (peak expiratory flow). Your lungs will not work as well when you are around a trigger.
  • Being tested for allergies. If you have allergies, the substances to which you are allergic can trigger symptoms.

An asthma trigger is something that can decrease lung function and lead to sudden difficulty breathing and other symptoms of an asthma attack. When you are around a trigger, you are at increased risk for an asthma attack. A severe attack may mean you have to go to the hospital.

Some triggers are substances you may be allergic to (allergens). These triggers may include:

Other triggers are not allergens—they can cause asthma symptoms, but you are not allergic to them. These include:

  • Cigarette smoke and air pollution.
  • Upper respiratory infections such as colds, influenza (flu), and sinusitis.
  • Exercise. Many people with asthma have symptoms when they exercise.
  • Dry, cold air.
  • Medicines, such as beta-blockers, aspirin, and other nonsteroidal anti-inflammatory drugs (NSAIDs).
  • In adults, hormones, including those involved in pregnancy and menstrual periods. Your symptoms may change just before or during periods.
  • Gastroesophageal reflux disease (GERD). Some experts debate whether GERD makes asthma worse. Studies have shown conflicting results as to whether GERD triggers asthma.1

Test Your Knowledge

A trigger is anything that can lead to an asthma attack.


Identifying asthma triggers helps you know what increases your asthma symptoms. If you avoid triggers, you may be able to:

  • Avoid an asthma attack altogether.
  • Reduce the length and severity of an asthma attack.

Test Your Knowledge

Avoiding asthma triggers can help you avoid an asthma attack or reduce its length and severity.

  1. Identify possible asthma triggers. A trigger is anything that can lead to an asthma attack. When you are around something that triggers your symptoms, keep track of it. This can help you find a pattern in what triggers your symptoms. Record triggers in your asthma diaryClick here to view a form.(What is a PDF document?) or on your asthma action plan.
  2. Monitor your lung function. A trigger may not always cause symptoms. But it can still narrow your bronchial tubes, which makes your lungs work harder. To identify triggers that do not always cause immediate symptoms, measure your peak expiratory flow (PEF) throughout the day. PEF will drop when your bronchial tubes narrow, so your PEF will drop when you are near things that trigger symptoms. Measure your PEF when you are around common irritants such as pollens and smoke to see if they are triggers.
  3. Be tested for allergies. Skin or blood testing may be used to diagnose allergies to certain substances. Skin testing involves pricking the skin on your back or arms with one or more small doses of specific allergens. The amount of swelling and redness at the sites where your skin was pricked is measured to identify allergens to which you react. If your PEF drops when you are near an allergen, consider being tested for this allergen.
  4. Share your trigger record with your doctor. After you have found some things that may trigger your asthma, you and your doctor can devise a plan for how to deal with them.

Test Your Knowledge

Monitoring your lung function and being tested for allergies are two ways you can identify asthma triggers.


Now that you have read this information, you are ready to start identifying your asthma triggers. Let your doctor know of any triggers you discover.

If you have questions about this information, take it with you when you visit your doctor.

If you would like more information on asthma, the following resource is available:


Asthma and Allergy Foundation of America (AAFA)
1233 20th Street NW
Suite 402
Washington, DC 20036
Phone: 1-800-7-ASTHMA (1-800-727-8462)
Email: [email protected]
Web Address:

The Asthma and Allergy Foundation of America (AAFA) provides information and support for people who have allergies or asthma. The AAFA has local chapters and support groups. And its Web site has online resources, such as fact sheets, brochures, and newsletters, both free and for purchase.

Return to topic:


  1. Gibson PG, et al. (2003). Gastro-esophageal reflux treatment for asthma in adults and children. Cochrane Database of Systematic Reviews (1). Oxford: Update Software.

ByHealthwise Staff
Primary Medical ReviewerJohn Pope, MD - Pediatrics
Specialist Medical ReviewerLora J. Stewart, MD - Allergy and Immunology
Last RevisedMarch 14, 2013

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