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| 1. Definitions / 2. Symptoms | |
What is Allergic RhinitisDefinitionAn allergic reaction occurs when the body's immune system overreacts to substances in the environment, called allergens. Allergic rhinitis is one type of allergy that occurs when an allergen comes in contact with the lining of the nose, or mucous membrane. This contact causes swelling and the secretion of excess mucus. | |
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