What's an Asthma Trigger?

Triggers are things that make a person's asthma worse. Being exposed to your triggers — for example, pet dander, exercise, or smoke — can lead to an asthma flare-up and coughing, wheezing, and shortness of breath.

Different people have different triggers. Some have one or two triggers; others have a dozen. Triggers are sometimes seasonal — like pollen in the spring. Some teens with asthma may stop reacting to certain triggers as they get older.

Common triggers include:

  • allergens (things that cause allergic reactions, like animal dander and pollen)
  • irritants in the air (like perfume, smoke, and air pollution)
  • weather conditions
  • exercise
  • colds or the flu

What's an Allergen?

Allergens are the things people can be allergic to, like mold; dust mites; cockroaches; pollen; and animal dander (skin flakes), saliva, urine, and feathers. Allergens are one of the most common asthma triggers. If you think you might have an allergy, talk to a parent or doctor about getting allergy testing.

How Can I Avoid Allergens?

Avoiding allergens is the first step. It isn't possible to avoid everything, but here are three tips to try:

  1. Keep your room as clean and dust free as possible. This means vacuuming and dusting weekly and getting rid of clutter. Your old stuffed animals and track ribbons may need to go into a box in the attic.
  2. Wash your sheets weekly in hot water and get rid of feather pillows and comforters. You can get special covers for your mattress, box spring, and pillows that will help too.
  3. Get rid of carpets and curtains. Rugs, carpeting, and other heavy fabrics can trap allergens that make you sick.

Your doctor can give you other ideas. If you have allergies that make your asthma worse, you might need to take allergy medicine or have allergy shots. Your doctor will let you know.

What's an Irritant?

For most people, irritants aren't a serious problem. But for people with asthma, they can lead to flare-ups.

Common irritants include:

  • perfumes
  • aerosol sprays
  • cleaning products
  • tobacco and wood smoke
  • paint or gas fumes
  • air pollution

Even things that may seem harmless, like scented candles or glue, are triggers for some people.

How Can I Avoid Irritants?

If you notice that a household product triggers your asthma, ask your family to switch to an unscented or nonaerosol version of it. If smoke bothers you, people smoking around you will be a trigger. But a fire in the fireplace or woodstove can be a problem too.

If outdoor air pollution is a trigger for your asthma, running the air conditioner can help. Check air quality reports on the news to see which days might be bad for you. When outdoor air quality is very bad, stay in air-conditioned comfort, whether it's at your house or the mall.

How Can I Prevent Illneses?

Colds or the flu are hard to avoid. The best prevention is washing your hands regularly and avoiding people who are sick.

An annual flu shot is now recommended for everyone above the age of 6 months. This is especially important for people with asthma, who are at greater risk for serious complications if they get the flu. Ask your doctor to include instructions on what to do if you start feeling like you're getting a cold or the flu.

How Can I Cope With Weather Changes?

Wind can stir up pollens and molds. Rain can wash pollen from the air, so the pollen count might be lower right after it rains. But lots of rain can make the trees and grasses produce more pollen later on. Very cold or very hot weather may trigger asthma. So can humidity or very dry air.

If you know that some kinds of weather make your asthma worse, follow the forecast. Take steps to protect yourself if you know the weather is going to cause problems for you. Your asthma action plan should say what to do.

What Is Exercise-Induced Asthma?

Some people with asthma have only one trigger: exercise. Along with allergens, exercise is one of the more common triggers.

Luckily, exercise is the one trigger you don't have to avoid. With help from their doctors, people with asthma can safely get the exercise they need to stay healthy and well. Talk with your doctor about what to do before, during, and after exercise.

There's one step you'll want to take no matter what your triggers are: Keep your quick-relief medicine with you at all times.

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