Indoor allergy symptoms and signs you might have them

An allergic reaction happens when your body detects a small substance that your immune system classifies as a threat. These small but powerful antigens are called allergens. The reaction can happen when you inhale allergens or when allergens land on your skin. Your cells release chemicals called histamines that cause a reaction — which causes allergy symptoms.1 

Common allergy symptoms include:


runny nose

itchy nose

images of people in their homes

Allergy triggers and where to find them

The most common indoor allergy triggers are dust mites, animal dander, cockroaches, and mold.1 Exposure to these allergens can trigger your immune system to release histamines and other chemical mediators, resulting in allergic rhinitis.2

Dust mites

One of the most prevalent triggers are dust mites — microscopic pests that love the indoors and warm humid environments such as bedding, upholstered furniture, and carpet.1

How to control dust mites:1

Keep surfaces clean

Avoid wall-to-wall carpet — try throw rugs that can be washed regularly

Place mattresses, box springs, and pillows in allergen-resistant fabric covers

Wash bedding, pillows, and stuffed toys weekly in hot water (at least 130°F) and dry in a hot dryer

Use a dehumidifier or air conditioner to reduce humidity


Indoor mold and mildew flourishes in damp places such as basements, bathrooms, and anywhere leaks occur, such as underneath the kitchen sink.1

What to do about mold:1

Reduce moisture in damp areas with proper ventilation

Clean humidifiers and dehumidifiers to prevent mildew from forming

Fix leaks quickly

Don’t place carpet over concrete or in damp places

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

Animal dander

While some pet breeds are deemed hypoallergenic, there are none that are really 100% hypoallergenic. Beyond fur, allergens live in animal saliva, pet dander (dead skin flakes), and urine. Typically, pet allergy symptoms start within minutes of contact.1

Some ways to manage pet allergens:1

Minimize physical contact with animals and wash off after handling them

Keep pets off of clothing and furniture fabrics

Vacuum carpets and keep hardwood floors, tile, and linoleum clean

If you have hamster, mouse, guinea pig, or rabbit allergies, let someone without allergies clean the animal’s cage


While often found in densely populated areas, cockroaches are almost anywhere.1 The World Health Organization identifies 12 distinct allergens carried by cockroaches.3

How to squash cockroach allergens:1

Schedule a regular extermination service

Block all areas where they can enter your home — every window, crack, and crevice

Repair leaky faucets and pipes

Keep surfaces crumb-free

Use lidded waste bins

Seal open food — including pet food

images of people in their homes

Extra tips to prevent indoor allergies

There’s no way to completely avoid exposure to allergens, but it’s important to minimize it when possible. Be mindful of indoor allergens when you're inside — for instance in your living room, garage, basement, attic, or even in the car. Prolonged exposure to indoor allergens is a risk factor for allergic respiratory diseases such as asthma.3

Some more ways you can reduce exposure to allergens:4

Keep indoor areas well ventilated — use fans to increase airflow

Use air purifiers with certified allergy and asthma filters

Keep windows and doors closed when pollen counts are high

Check the pollen forecast regularly if you experience seasonal allergies

Wear a mask when cleaning

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1.  Andrew Moore, MD, reviewed. Indoor Allergens, American Academy of Allergy, Asthma & Immunology (, September 28, 2020. Accessed March 2, 2022.

2.  Editors. Hay Fever / Rhinitis, American Academy of Allergy, Asthma & Immunology ( Accessed March 2, 2022.

3.  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. Accessed March 2, 2022.

4.  Asthma and Allergy Foundation of America, Ed. Control Allergens to Improve Indoor Air Quality, Reviewed by Medical Scientific Council, 2015. Accessed March 2, 2022.

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