Understanding Asthma Triggers

Understanding Asthma Triggers

Find Services and other Health Information from A-Z

Understanding Asthma Triggers

Triggers are things thatcause you to have asthma symptoms. Some triggers you can avoid completely. Others you can anticipate and adjust to. Use this sheet to help you identify your triggers.

Man holding a light brown pomeranian dog.

What Are Triggers?

Triggers irritate your lungs and lead to asthma flare-ups. Some examples are:

  • Irritants, such as tobacco smoke or air pollution. These are a concern for all people with asthma.

  • Allergens or substances that cause allergies, like pets, dust mites, or pollen.

  • Special conditions, such as being ill with a cold or the flu, or certain kinds of weather. These differ from person to person.

  • Exercise can trigger asthma in some people. If exercise is one of your triggers, you can learn how to exercise safely.

What Triggers Your Asthma?

Which of these common triggers cause your asthma to flare up? Check all that apply to you.


Checkbox. Tobacco smoke (smoking or second-hand smoke)

Smoke from fireplaces

Vehicle exhaust

Smog or air pollution

Aerosol sprays

Strong odors, such as perfume, incense, or cooking odors

Household cleaners, such as ammonia or bleach





Dust or dust mites




Other Triggers:

Cold air

Hot air

Weather changes


Certain foods or food ingredients (such as sulfites)


Emotions, such as laughing, crying, or feeling stressed

Illness, such as colds, flu, and sinus infections

Allergies and Allergy Treatment

People with asthma often have allergies.  If you have allergies, or suspect you have them, talk with your healthcare provider about testing and treatment options. Allergy testing can determine exactly which allergens affect you. Types of tests include:

  • Skin tests. A small amount of each allergen is applied to the skin. Sites are then examined for an allergic reaction (redness, swelling, or itching). In general, the greater the reaction, the stronger the allergy.

  • Blood tests. An allergen is added to a blood sample. If you have a reaction, it shows sensitivity to the allergen.

Exposing a person to gradually increasing amounts of an allergen can help the body build up a tolerance. This is the purpose of allergy shots, or immunotherapy. For this therapy, injections are given over a period of years. At first, injections containing a very small amount of allergen are given about once a week. As treatment continues, the amount of allergen is gradually increased to a maintenance level. Eventually, injections are given less often. This therapy can take up to a year to start working, but can be very effective for long-term management of certain allergies.