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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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Kids' Allergy Shots Cut Health Care Costs

Kids with hay fever can benefit significantly if they take allergy shots, or allergen immunotherapy. The shots also help keep health care costs down.

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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.

Allergy Basics