Indoor Allergies: Causes, Symptoms and Relief

Make indoors more comfortable by reducing allergy triggers

A woman following exercises on her computer in her living room.

There’s no place like home - for allergies! Just stepping indoors — at home, work, or school — exposes you to numerous allergens. An allergen is any substance which produces an allergic reaction. Millions of people worldwide suffer from year-round indoor allergens - yes, it's just that common.

The most common sources of indoor allergies are dust mites, fungi (mold), mammals (both your pets and invasive rodents), and cockroaches.

Let's make it simple: the cleaner your home, the stronger your defense against indoor allergies.

Throughout this page, you will find information about:

Signs and symptoms of indoor allergies

An allergic reaction is the result of your immune system going on the defensive. When it detects an allergen, it produces antibodies called Immunoglobulin E (IgE). In response, your cells release chemicals to fight the allergens, which result in your allergy symptoms.

The most typical symptoms of indoor allergies include:

  Runny nose

  Itchy, red, and/or watery eyes



  Hives, rash, or other types of skin irritation

Here’s where most indoor allergens hide:

  Damp and humid areas

  Indoor plants


  Pillows and bedding

  Plush furniture

  Plush toys

  Unsealed mattresses

  Wall-to-wall carpet

The most common indoor allergy triggers and what to do about them

Dust mites

More than 95% of the allergens associated with mites are inhaled. Mite-contaminated food can also be a source of allergic reactions.

How to control dust mites:

  Keep surfaces clean and uncluttered

  Avoid wall-to-wall carpet: use low-pile carpets, washable rugs, hardwood, linoleum, or tile

  Avoid heavy drapes

  Avoid overstuffed furniture

  Use sealed, allergen-resistant covers on your pillows and mattress

  Wash bedding, pillows, and stuffed toys in hot water; dry them in a hot dryer

Indoor mold:

The common indoor mold and mildew that cause allergies thrive in dampness. You’ll find them in moist basements, bathrooms, or anywhere with leaks. Mold can cause a variety of allergic reactions, from minor irritation to severe asthma.

How to reduce mold:

  Reduce moisture in the bathroom, kitchen, and basement

  Don’t run showers too long before hopping in

  Use dehumidifiers

  Limit the number of house plants, and ensure proper drainage

  Fix leaks quickly

  Remove mold from hard surfaces with water and detergent or, if necessary, 5% bleach; let them dry completely

Pet dander:

There are no breeds of dogs or cats that are 100% allergen-free — not even the hairless ones. That’s because you don’t react to fur, but to allergens in saliva, dander (skin flakes), or urine.

How to manage pet dander:

  Avoid direct contact with pets

  Keep pets out of your bedroom

  Wash and change pet beds and toys often

  Bathe and brush your pets often — and wear a mask when you groom them

  Wash your hands after handling pets

  Frequently wipe and vacuum spaces where your pets spend time

  Before getting a pet, ask your allergist to determine if you are allergic to animals


The World Health Organization identifies 12 distinct allergens carried by cockroaches.

How to control cockroaches:

  Cover food, garbage, and recyclables; take the trash out quickly

  Use poison baits, boric acid, and traps instead of chemicals, which may irritate your sinuses and/or asthma

  Block crevices, wall cracks, and windows where they enter

  Fix and seal leaks

  Keep food in lidded containers

  Put away used pet bowls and uneaten food

  Vacuum and sweep after meals

  Wash dishes immediately after use

  Clean under stoves, refrigerators, or toasters where crumbs can accumulate

  Wipe off the stove, cupboards, and other kitchen surfaces regularly

Woman sitting by the window with cup

Allegra® is here to help

Allegra® offers multi-symptom relief from sneezing, runny nose, itchy, watery, red eyes and itchy nose/palate/throat. For added relief from nasal congestion associated with seasonal allergies, there's Allegra®-D. Allegra®, Live your Greatness

Tips and tricks to minimize indoor allergens

It’s nearly impossible to completely avoid indoor allergens - but there are ways you can reduce them.

  • Keep the air as clean as possible
    • Increase the flow of outdoor air
    • Reduce humidity
    • Use air cleaners with certified allergy and asthma filters
    • Vacuum frequently with certified allergy and asthma filters
  • Wear a mask while doing housework
    • Leave the house for several hours after cleaning it

    1. Andrew Moore, MD, reviewed. Indoor Allergens, American Academy of Allergy, Asthma & Immunology [], February 28, 2020. Reviewed on May 20, 2021.

    2. Anna Pomés, Martin D. Chapman, Sabrina Wünschmann. Indoor Allergens and Allergic Respiratory Disease, PMC/US National Library of Medicine, National Institutes of Health, June 2016. Reviewed on Oct. 5, 2021.

    3. Asthma and Allergy Foundation of America, Ed. Control Allergens to Improve Indoor Air Quality, Reviewed by Medical Scientific Council, 2015. Reviewed on Oct. 5, 2021.

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