Indoor Allergens and Asthma

Indoor allergens are found indoors and can make your asthma symptoms harder to manage. The best way for you to control your asthma is to avoid these allergen sources.


Many people love and consider pets as members of their families. However, for some people, household pets can be harmful to their health and asthma. These people have a pet allergy.

Pet allergies are a common form of indoor allergen. The source of the problem is allergens in the fur, feathers, urine, or saliva of the animal. These allergens, however, are not limited to homes. Pet allergens can attach themselves to your fabrics and clothes. As a result, you do not need to have a pet be exposed.

If a pet allergen is a trigger for your asthma, you may experience: 

  • Quick, shallow breathing or feeling like you’re unable to catch your breath.
  • A persistent cough
  • Swelling of the tongue, face, or mouth, or a life-threatening swelling of the airways (“anaphylaxis”)
  • Rash, hives, itchy, or flaky skin
  • Watery or itchy eyes
  • Sinus congestion or runny nose 
Managing Pet Allergies

Unless you have a severe allergy 1, you may not have to get rid of your pets to manage your asthma. You can limit your exposure to this indoor allergen. 

  • Move pets’ cages from the bedroom and ventilation.
  • Block your pet from entering your bedroom
  • If you can, remove all of your indoor carpeting. 
  • Regularly clean and vacuum your home and furniture
  • Use an allergy medication along with your asthma medications.
  • Wash your hands after playing with and touching your pets.

Dust Mites

Dust mites are a microscopic source of indoor allergen. They tend to live in tightly woven fabrics, like furniture, mattresses, bedding, pillows, and stuffed animals. The source of the allergen is in the proteins found in their feces and dead bodies.

The amount of time it takes for your body to react to your grass allergy varies. Some of you will have mild asthma symptoms, while others have life-threatening reactions. Being aware of your asthma triggers allows you to avoid life-threatening reactions and better manage your health. 

  • Coughing 
  • Chest tightness
  • Wheezing
  • Runny nose
  • Trouble sleeping because of respiratory symptoms
Limit Your Exposure to Dust Mites

Dust mite allergens are only airborne for 10-20 minutes. Also, a single exposure is not enough to trigger your allergic response 2. However, dust mites can live in homes and public spaces. Even though you cannot control your exposure in public environments, you can control your exposure to this indoor allergen in your home. 

  • Control the humidity in your home. The best practice is 45-50%
  • Wash and change your bedding (sheets, pillowcases, mattress pads) weekly
  • Use finely woven bedding and mattress covers
  • Remove indoor carpets
  • Replace your curtains with blinds
  • Dust mites have no protection against sunlight. Therefore, you can kill them by exposing tightly woven fabrics, like mattresses, to sunlight
  • Use a high-efficiency particulate air (HEPA) filter to trap allergen particles.


Cockroaches are unwanted houseguests that can also affect your asthma. The source of the cockroach allergen is in their saliva, fecal matter, skin, and body parts. People with cockroach allergies 3 have higher risks for developing asthma and worsening asthma symptoms. 

  • Runny or stuffy nose
  • Coughing
  • Watery eyes
  • Dry, itchy, or scaly skin
  • Itching in your Eyes, nose, or throat
  • Sneezing
  • Trouble breathing
Limit Your Exposure

Cockroach allergens are in four out of every five homes. However, this does not mean that you cannot limit your exposure to this allergen.

  • Use non-toxic roach bait
  • Use your asthma therapy as needed
  • Minimize piles and clutter in your home
  • Seal cracks and holes 
  • Keep your food containers closed and trash cans sealed 
  • Fix leaks inside of your homes, as stagnant waters attract cockroaches and other insects
  • We recommend integrated pest management (IPM) 4


Molds grow in environments with too much moisture, such as leaking pipes, humid bathrooms, and damp carpets. Mold spores are the source of this indoor allergen. For people with a mold allergy or sensitivity 5, inhaling mold spores causes asthma symptoms or attacks. 

  • Airway tightening/constriction 
  • Coughing 
  • Wheezing 
  • Shortness of breath 
  • Worsening of your asthma symptoms
Avoid Molds

Managing your exposure to mold is crucial for managing your asthma.

  • Maintain your heating, ventilation, and air conditioning systems
  • Use a humidity monitor and keep indoor levels between 30-50%
  • Open your bathroom windows when you shower
  • Repair indoor water damage
  • Avoid grasses in the summer when mold spores may be present.