What Are Allergies?

Allergies are caused by the body's overzealous reaction to normally harmless substances. Allergies can be triggered by pollen, animal dander, mold, dust, and insect droppings, or by certain foods or insect stings. Upper respiratory allergy symptoms include runny nose, itchy eyes, coughing, wheezing, and sneezing.

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Your New Allergy Survival Guide

It’s not your imagination: Symptoms really have been more severe this year than ever before. Here, the surprising reasons why—and the latest ways to nip them in the bud.