Indoor Allergens

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Indoor allergen facts

  • House dust is a mixture of components that can cause allergies.
  • Particles and debris from dust mites are common causes of allergies from house dust.
  • Dust mites thrive in warm, humid places.
  • Cockroach allergy can be a major factor in serious asthma and nasal allergy.
  • Symptoms of hay fever (allergic rhinitis) and asthma can be caused by the inhalation of airborne mold spores.
  • The "dander," or skin shedding of an animal, is more potent in causing allergic reactions than the animal's fur or hair.
  • About 6% of the U.S. population is allergic to cats.
  • Indoor plants, especially those that are kept in damp wicker baskets, are a source of molds.

What are allergens?

Allergens are substances that are foreign to the body and can cause an allergic reaction in certain people. Allergens are everywhere in the world around us. Examples of common allergens are pollen, foods, and mold.

Your living environment may contain a variety of animal and plant life, most of which can become a source for allergens, the triggers of allergic reactions. Pollens are the main cause of seasonal allergic rhinitis. However, if your nasal stuffiness, sneezing, watery eyes, and constant postnasal drip bother you year-round, then you most likely have nonseasonal hay fever, sometimes referred to as perennial allergic rhinitis. This condition is typically caused by indoor allergens such as dust mites, cockroach parts, mold, and animal dander.

Understanding the nature and location of common and indoor sources of allergy is fundamental. The key to managing allergies that are caused by indoor allergens involves reducing your level of exposure to them or avoiding them entirely, if possible.

This article describes some of the most common sources of allergens found inside the home environment.

What are symptoms and signs of reactions to indoor allergens?

Indoor allergens can cause symptoms in susceptible people. Seasonal allergic rhinitis can be caused by indoor allergens and manifests as nasal congestion, runny nose, watering of the eyes, sneezing, and postnasal drip. Symptoms of asthma, including wheezing or difficulty breathing, can also occur in susceptible individuals.

Allergic reaction to indoor allergens can also cause conjunctivitis, an inflammation of the lining membranes of the eyes. Symptoms of this condition include red, watery, and itching eyes.

Allergic symptoms involving the skin include eczema, or allergic dermatitis, characterized by a skin rash associated with itching. This usually results from direct contact with the allergen.

Medically Reviewed by a Doctor on 10/22/2015

Allergy Pictures Slideshow: 10 Common Allergy Triggers

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Indoor Allergens - Dust Mites at Home Question: How do you control dust mites at home? Do you clean frequently?
Indoor Allergens - Cockroaches Question: What do you do to control cockroaches in your home?
Indoor Allergens - Pollens and Houseplants Question: Which houseplants have been a source of mold or allergens at your house?
Indoor Allergens - Pets Question: How do you deal with allergies caused by household pets? Have you ever had to give away a pet?

Allergy Symptoms and Signs

Allergies are exaggerated immune responses to environmental triggers known as allergens. Allergies are very common, and about 50 million people in North America suffer from allergies. One of the most common forms of allergy is allergic rhinitis ("hay fever"), which produces symptoms like:

  • nasal congestion,
  • itchy and watery eyes,
  • sneezing,
  • stuffy or runny nose,
  • scratchy or sore throat,
  • throat clearing,
  • cough from postnasal drip.