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Allergies Health Center

Allergies Overview

At least one out of every 5 Americans suffers from allergies. Common causes of allergy symptoms include food allergies such as peanut allergy or milk allergy, and seasonal allergies resulting from grass, weed, tree pollen, or various molds. Cat allergies and dog allergies can also cause miserable symptoms such as itchy eyes, sneezing, nasal congestion, and wheezing. Allergic skin conditions can cause a rash and itchy skin.

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Pets, Dust May Worsen Ragweed Allergies

People who have hay fever and who also have an allergy to cats, dogs, dust mites, or grass pollen have hay fever symptoms that are more severe and occur earlier on, according to a new study.

Allergy Basics

What Is an Allergy?

Allergies are an abnormal response of the immune system. People who have allergies have an immune system that reacts to a usually harmless substance in the environment. This substance (pollen, mold, animal dander, etc.) is called an allergen.

Allergies are a very common problem, affecting at least two out of every 10 Americans.

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Show or hide information about video: The Truth About Allergies   The Truth About Allergies

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We separate fact from fiction about identifying allergy triggers and what you can do to stop them in their tracks.

Watch Video: The Truth About Allergies (opens in a new window)

Show or hide information about video: Keep Your Home Allergy Free

  Keep Your Home Allergy Free

Show or hide information about video: Allergy-Free Spring Cleaning

  Allergy-Free Spring Cleaning

Show or hide information about video: Outdoor Exercise and Allergies   Outdoor Exercise and Allergies

Show or hide information about video: Busting Allergy Myths   Busting Allergy Myths