Avoiding asthma and allergy triggers

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What is an asthma or allergy trigger?

This is anything that causes asthma or allergy symptoms or makes symptoms worse. It's important to know what your triggers are. That way, you can avoid them so your symptoms don't get worse.

What are some common triggers?

Common asthma triggers are:

Getting sick, like with a cold, the flu, COVID-19, or a lung or sinus infection
Cigarette smoke
Stress
Strong cleaning products, such as bleach
Strong perfumes or scents
Air pollution
Certain medicines, such as aspirin and other medicines for pain or fever
Exercise
Very cold and dry air
Thunderstorms

Not all these things are triggers for everyone. For example, 1 person's symptoms might only be triggered by having a cold or exercising. Another person might have many triggers.

Some people are allergic to things in the environment. These are called "allergic triggers." Examples include:

Dust mites – These are tiny bugs that are too small to see. They live in beds, couches, carpets, and other places in homes.
Mold – Mold can grow in basements, showers, and other damp and wet places.
Dogs and cats – People can be allergic to animal saliva, urine, or dander (flakes of dead skin).
Pollen from trees, grass, and weeds
Cockroach droppings
Mice and rats

How do I know what my triggers are?

You might already know what makes your asthma symptoms worse. But if you don't, talk with your doctor or nurse. They can help you figure it out by talking with you and asking you questions.

Your doctor might do allergy tests to see if you have allergic triggers. These include blood tests or skin tests. During a skin test, the doctor puts a drop of a substance you might be allergic to on your skin, and makes a tiny needle prick in your skin. Then, they watch to see if your skin turns red and bumpy.

What should I do when I find out what my triggers are?

Try to stay away from your triggers. For example, if cigarette smoke makes your asthma symptoms worse, avoid people who are smoking. If you smoke, get help to quit.

Here are other things you can do:

Wash your hands often to avoid getting sick with an infection. Some people also wear a mask in crowded places.
It's important to get the COVID-19 vaccine. This lowers the risk of severe illness if you do get COVID-19. You should also get a flu shot every year. Some people also need to get a vaccine to help prevent pneumonia.
Stay indoors when air pollution levels are high. Don't exercise near a busy road.
On winter days when the air is cold and dry, cover your mouth and nose with a scarf.
Avoid using bleach and other strong cleaners.

If you have allergic triggers, try to avoid the things you are allergic to:

To avoid dust mites, cover your pillows and mattresses with special covers that keep dust mites away. Remove carpets from your bedroom. For more tips, see the table (table 1).
To avoid mold, regularly clean any areas that tend to grow mold, such as sinks and tiles. To keep more mold from growing, use a dehumidifier or air conditioner, fix leaky plumbing, and remove carpets that were damaged by water. You can also remove indoor plants, as well as other items that might have gotten damp and grown mold, such as old books or bedding.
To avoid animal saliva, urine, or dander, you can remove the pet from your home and clean your home after the animal has gone. If this is not an option, there are other things you can try (table 2).
To avoid pollen, stay inside more during the times of year when your asthma symptoms are worse. Keep windows closed to prevent pollen from getting inside your home. When you do go outside, shower or bathe after you come back in. This can help remove any pollen from your body and clothing.
To keep cockroaches away, don't let garbage or dirty dishes pile up. If possible, fix leaky plumbing so there are no puddles of water. If you have cockroaches, use traps to kill them, or call an exterminator.
To get rid of mice or rats, set traps or call an exterminator.

What if I can't avoid my triggers?

Talk with your doctor or nurse about what you can do.

Exercise is an example of a trigger you should not avoid, because exercise keeps you healthy. To prevent asthma symptoms when you exercise:

Take an extra dose of your quick-relief inhaler medicine before exercising.
Warm up slowly before each exercise session.
Avoid exercising outdoors if it is very cold out.

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table 1: Tips for avoiding dust mites in your home
First: Bedrooms
Cover your pillows and mattresses with special zippered covers that keep dust mites away from you. Every week, wash your sheets, pillowcases, and blankets in hot water with detergent, or dry them in an dryer on the hot setting. If possible, use a comforter or blanket that can be washed. Use washable, vinyl, or roll-type window covers. Avoid curtains and drapes. Remove clutter, stuffed animals and other soft toys, bed skirts, and fabric-covered furniture. If you cannot take stuffed animals out of the bedroom, wash them every week. If possible, remove carpets. Instead, use area rugs that can be cleaned or washed.
Second: Rest of house
Try to reduce the amount of fabric-covered furniture you have, especially old sofas. If possible, replace carpets with (noncarpet) flooring. This includes carpets on concrete slabs or over poorly ventilated crawl spaces. Every week, vacuum the house with a vacuum that has a "HEPA filter." Use a mop, rather than a broom, to clean floors. Use washable, vinyl, or roll-type window covers. Make sure the humidity in the home is less than 50%. Do not use a humidifier.
Third: Changing houses^*
People with allergies and asthma do not usually need to move, except if they live in a basement or in a home that is very damp and wet. If you are allergic to dust mites or mold, you might have fewer symptoms if you move to: An apartment on or above the second floor A home with wooden floors and bedrooms on the second floor

HEPA filter: high-efficiency particulate air filter.

* The average family in the US moves about every 4 years.

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table 2: Tips for avoiding animal allergens (urine, saliva, or dander) in your home
If possible, remove animals from your home
Keep any animals outside, in the garage, or in a kennel. Keeping them only out of certain rooms in the house might help a bit, but does not remove animal allergens from your home. After you remove the animal, clean your home thoroughly.
If you cannot remove the animals from your home, try these steps
Use an air filter with a "HEPA" filter, but remember that air filters help only a little. Most of the animal allergens in your home are not floating in the air. Air filters only remove allergens that are floating in the air. Reduce the number of things in your home where allergens can build up. Examples include carpets, fabric-covered furniture, and drapes. Replace these with bare floors, furniture that is not covered with fabric, and window blinds. Every week, vacuum with a vacuum cleaner that has a "HEPA" filter. If you are allergic to your dog, bathing your dog every week might help reduce your symptoms. If you are allergic to your cat, bathing your cat will probably not reduce your symptoms.

HEPA: high-efficiency particulate air filter.

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