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Asthma triggers

It's important to learn your asthma triggers and take steps to avoid them.

Asthma flare-ups usually begin because something bothers your lungs. These aggravating agents are called asthma triggers.

Triggers can come in many forms—and different people are sensitive to different triggers.

According to the American Academy of Allergy, Asthma & Immunology and the National Heart, Lung, and Blood Institute, the following are examples of triggers:

Allergens are substances that cause an allergic response in the body. Common allergens include pollens, foods, dust, cockroach droppings, mold and animal dander—which comes from the skin, hair or feathers of animals.

It's important to try to avoid any allergens that trigger your asthma.

Irritants are things in your environment that can sometimes bother the airways and trigger asthma. They include:

  • Smoke from tobacco or wood. Tobacco smoke is an especially common irritant. No one should smoke in the home of a person who has asthma.
  • Airborne particles, such as dust, vapors, gases or fumes.
  • Strong odors from painting, cooking, perfumes or cleaning products.
  • The weather. Cold air, strong winds or shifts in temperature and humidity can all contribute to an asthma flare-up.

Infections, such as colds, sinusitis and viral pneumonia, may trigger an asthma flare-up by irritating the airways, nose, throat, lungs and sinuses.

Exercise. Exercise-induced asthma is more likely if a person exercises in cold, dry air, breathes through the mouth or engages in prolonged, strenuous activities such as long-distance running.

But even though exercise can be a trigger, people with asthma can (and should) stay active. A doctor can help you choose activities that are less likely to cause flare-ups.

Reflux disease. Gastroesophageal reflux disease (GERD) causes stomach acid to back up into the esophagus. GERD may lead to heartburn, belching and asthma attacks. Treating GERD may help reduce asthma symptoms.

Medicines. Aspirin and related drugs, as well as some medicines used to treat heart disease and high blood pressure, can trigger asthma. People who have asthma should talk to their doctors before taking any over-the-counter medicines.

Food allergies. Allergies to foods such as peanuts and shellfish can sometimes trigger asthma.

Avoid the problem

Every person has his or her own asthma triggers. Your doctor can help you identify yours and find ways to avoid them. Your doctor can also help you develop an asthma treatment plan that helps prevent symptoms and provides for relief when they do occur.

Reviewed 7/3/2023

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