Reduce Asthma Triggers

An asthma trigger is a thing, activity or condition that makes asthma worse. When you come in contact with a trigger it can cause a sudden worsening of symptoms which is often called an asthma attack, episode or flare-up.

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Common asthma triggers include respiratory infections, allergens, irritants, exercise, and emotions. Knowing what causes your asthma symptoms is an important step to controlling your asthma. Allergy testing may help you identify your triggers. Your health care provider can help you recognize what makes your asthma worse, and help find simple solutions to reduce and avoid asthma triggers.

The most common asthma triggers include:

Medical Conditions

Medical ConditionsRespiratory Infections, such as a cold, flu, or sinus infection, are the most common cause of asthma symptoms leading to an asthma flare-up. Frequent hand washing and avoiding people who are sick will help to reduce your exposure to cold and flu. But, the best way to prevent influenza is to get a flu vaccine every year. To find a flu vaccine near you, visit the Flu Vaccine Finder. Medical conditions such as Acid Reflux can also worsen asthma symptoms.

Respiratory Infections (colds, flu, sinus infections)
Pregnancy hormones
Acid Reflux

Food & Medicines

Food & MedicinesAsthma can be triggered by food allergies as well as medicines. Discuss any over-the-counter or prescription medicines you take such as aspirin, fever-reducers or anti-inflammatories with your health care provider, along with any alternative therapies or herbal remedies that may have an impact on your asthma.

Common food allergies (peanuts and shellfish)
Non-steroidal anti-inflammatory drugs


SmokeAll types of smoke can make it hard to breathe – including smoke from cigarettes, wood burning fireplaces, burning leaves. If you smoke, you should make a plan to quit. If you don’t smoke, but live with someone who does, discuss ways to avoid or limit your exposure to tobacco smoke. The American Lung Association offers many ways to help smokers quit. Contact the American Lung Association Lung HelpLine at 1-800-586-4872 to speak with a smoking cessation&bsp;counselor.

Cigarette, cigar or pipe smoke
Fireplace, campfire or leaf burning smoke

Weather, Pollen, & Air Pollution

Weather, Pollen, & Air PollutionChanges in the season can bring on an asthma episode due to increased pollen in the air. Limit your time outdoors during high pollen times of the year such as spring and fall. Also, extreme temperatures (hot and cold) can trigger symptoms of asthma. Be prepared for the weather before you leave your home by checking the pollen count and air quality index.

Cold, windy, stormy weather
Sudden or extreme temperature changes
High humidity
Weeds, trees, grass
Air pollution, smog, vehicle exhaust and fumes


AnimalsDander and saliva from animals with fur or feathers can be an allergen for some and can cause asthma symptoms. Reduce your exposure to pet allergens by vacuuming and damp dusting weekly. Try to keep your pets out of the bedroom or other rooms where you spend a lot of time.

Cats, dogs, ferrets, hamsters, Guinea pigs, bunnies or mice


PestsPests in the home, workplace or school can impact your asthma. To reduce your exposure to these triggers, wash bedding regularly, fix leaks, store garbage outside, vacuum and dust weekly, as well as using allergen-proof pillow and mattress covers.

Dust mites
Rodents such as mice and rats


MoldMold is an allergen that can trigger asthma symptoms. You can reduce your exposure to mold by cleaning visible mold, throwing away moldy items, running a dehumidifier and using the exhaust fan when taking a shower. Clean mold with mild soap, how water and a strong brush.



ExerciseStaying active is very important to your overall health and wellbeing, especially for those with asthma. If you have exercise causes asthma symptoms, use your quick-relief medicine 15 – 30 minutes before physical activity if prescribed. Remember to monitor the air quality if you plan to exercise outside.

Walking, climbing stairs
Intense exercise


EmotionsEvery day comes with its ups and down emotionally. It’s important to remember that strong emotions can increase rapid breathing and trigger asthma symptoms. Stress, both personal and work-related, can be a major trigger as well.

Laughing or crying too hard
Feeling stressed or anxious

Strong Odors

EmotionsScents from perfumes, deodorants and cleaning supplies can affect a person with asthma. When possible, choose cleaning and personal care products that are odor and fragrance-free.

Cleaning products
Gas Stoves
Scented candles and incense
Air fresheners
Personal care products