If you have asthma, an asthma attack can happen when you are exposed to “asthma triggers.” Your triggers can be very different from those of someone else with asthma. Know your triggers and learn how to avoid them. Watch out for an attack when you can’t avoid the triggers. Some of the most common triggers are:

Tobacco Smoke

Tobacco smoke is unhealthy for everyone, especially people with asthma. If you have asthma and you smoke, quit smoking. “Secondhand smoke” is smoke created by a smoker and breathed in by a second person. Secondhand smoke can trigger an asthma attack.

Make your home a smoke-free zone. Encourage household members who smoke to quit. If you have asthma, people should never smoke near you, in your home, in your car, or wherever you may spend a lot of time.

Dust Mites

Dust mites are microscopic bugs that are in many homes. If you have asthma and are allergic to dust mites, they can trigger an asthma attack. To prevent attacks:

• Use allergen-proof mattress and pillowcase covers to make a barrier between dust mites and yourself.
• Don’t use down-filled pillows, quilts, or comforters.
• Wash your bedding weekly and dry it completely.
• Vacuum carpets, area rugs, and floors regularly using a vacuum equipped with a HEPA filter.
• Keep relative humidity levels in the home low, around 30- 50%.

Outdoor Air Pollution

Outdoor air pollution can trigger an asthma attack. This pollution can come from many sources, including factories, cars, or wildfire smoke. Wildfire smoke from burning wood or other plants is made up of a mix of harmful gases and small particles. Breathing in too much of this smoke can cause an asthma attack.

Pay attention to air quality forecasts on radio, television, and the internet and check your newspaper to plan your activities for when air pollution levels will be low.

Pests (e.g., cockroaches, mice)

Cockroaches and other pests are often found where food is eaten and crumbs are left behind. To control pests in your home:

• Remove as many water and food sources as you can.
• Clean dishes, crumbs, and spills right away.
• Store food in airtight containers.
• Keep trash in a closed container.
• At least every 2 to 3 days, vacuum or sweep areas that might attract cockroaches or mice.
• Keep counters, sinks, tables, and floors clean and free of clutter.
• Seal cracks or openings in cabinets, walls, baseboards, and around plumbing.
• Use pesticide baits and traps in areas away from children and pets, following manufacturers’ instructions.
• Avoid using sprays and foggers as these can cause asthma attacks.

Pets

Furry pets can trigger an asthma attack if you are allergic to them. If you think a furry pet may be causing attacks, you may want to find the pet another home. If you can’t or don’t want to find a new home for the pet, decrease your exposure by:

• Keeping pets out of bedrooms,
• Washing furry pets,
• Using an air cleaner with HEPA filter, and
• Using allergen-proof mattress and pillow covers.

People with asthma are not allergic to their pet’s fur, so trimming a pet’s fur will not help your asthma.

Mold

Breathing in mold can trigger an asthma attack whether or not you are allergic to mold. Indoor mold growth is often found in damp areas such as kitchens, bathrooms, and basements, or in areas where water damage has occurred. There are many types of mold which can be found in any climate. Get rid of mold in your home to help control your attacks.

To reduce mold exposure in your home:

• Dry damp or wet items within 24 to 48 hours to prevent mold growth.
• Fix water leaks, such as leaky plumbing, which let mold grow behind walls and under floors as soon as you can.
• Replace absorbent materials, such as ceiling tiles and carpet, if mold is present.
• Use an air conditioner or dehumidifier to maintain low indoor humidity.
• Get a small tool called a hygrometer to check humidity levels and keep them as low as you can—no higher than 50%. Humidity levels change over the course of a day, so check the humidity levels more than once a day.
• Scrub mold off hard surfaces with detergent and water. Dry completely.
• Empty and clean refrigerator and air conditioner drip pans regularly.
• Run the bathroom exhaust fan or open the window when showering.

Disinfectants

Some disinfectants can trigger an asthma attack. People with asthma should try to stay away when cleaners or disinfectants are being used and right after their use. Follow these precautions when cleaning or disinfecting places where people with asthma may spend time, such as homes, schools, or workplaces:

• Avoid overuse of products. To help limit your exposure to asthma triggers, follow a schedule for cleaning and disinfecting to prevent overuse of products.
• Use safer products. Any disinfectant can trigger an asthma attack, but you can take steps to reduce the chances of that happening:
  • Choose products for disinfecting that are less likely to cause an asthma attack, such as products with hydrogen peroxide (no stronger than 3%) or ethanol (ethyl alcohol). Ensure that products with hydrogen peroxide or ethanol do not contain other chemicals that can cause an asthma attack such as peroxyacetic acid or peracetic acid.
  • Avoid using bleach (sodium hypochlorite) or quaternary ammonium compounds in enclosed spaces and limit their use.
  • Avoid products with fragrances. The fragrances can trigger asthma attacks.
• Make sure there is enough air flow (ventilation).
• Use products safely and correctly.
• Avoid disturbing dust because it can be an asthma trigger.
• Move away from the trigger (such as the area that was cleaned)

Other Triggers

Infections linked to influenza (flu), colds, and respiratory syncytial virus (RSV) can trigger an asthma attack. Sinus infections, allergies, pollen, breathing in some chemicals, and acid reflux can also trigger attacks.

Physical exercise; some medicines; bad weather, such as thunderstorms or high humidity; breathing in cold, dry air; and some foods, food additives, and fragrances can also trigger an asthma attack.

Strong emotions can lead to very fast breathing, called hyperventilation, that can also cause an asthma attack.