What causes allergy symptoms?

A person with allergies has an immune system that treats ordinarily harmless proteins like plant pollen, pet dander, dust mites or peanuts as if they were dangerous invaders by producing antibodies to protect the body from harm. This sets off a complex series of chemical reactions that leave a wake of inflammation in their path.

The lining of the airways becomes irritated. Cilia, the tiny hairs that sweep allergens out of the airways, become bogged down with mucus and excess fluid, and allergy symptoms occur: runny nose, nasal congestion, postnasal drip, sneezing, coughing and shortness of breath; itchy, watery eyes; itchy, irritated skin. In some cases, symptoms can progress into life-threatening anaphylaxis.

Who’s at risk for allergies?

As many at 50 million people in the United States have some sort of allergy. The tendency to develop allergies is often – but not always – hereditary, passed down from generation to generation. However, not everyone in a family will be allergic to the same things – and some won’t be allergic at all!

Common allergies

People who have allergies are at increased risk of developing other allergic diseases such as asthma and eczema (allergic dermatitis). That’s why it’s important to get an accurate diagnosis and treatment plan.

New: Understanding Allergies: Feel Better. Breathe Better. Live Better — a comprehensive, 36-page magazine.



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