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Allergies Health Center

Allergies Overview

Allergy symptoms include itchy eyes and skin, sneezing, nasal congestion, wheezing, and rash. Seasonal allergies result from grass, weed, tree pollen, or molds. Cat and dog dander allergies are common. Food allergies include peanut or milk.

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Seasonal Allergy Symptoms

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, and animal dander, for example) is called an allergen.

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

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