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Allergies Health Center

Allergy Facts

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Spring goes into full bloom, yet you’re in real misery. Others fight battles with certain foods, chemicals, or airborne particles. What causes these reactions?

What Are Allergies?

This article explains the basics of an allergic reaction. Learn what happens when your immune system goes on high alert.

People with allergies also can develop red, swollen, and itchy eyes when exposed to their allergic triggers. 

If you've got allergies, you might wonder what to expect in the long term. Are you stuck with allergy symptoms, or will they get better? Or could they actually get even worse?

Are your allergies acting up? Get the facts on common allergy types.


Almost anything can trigger an allergy. Read this in-depth article.

The air you breathe, whatever touches your skin, anything you put in your mouth – it’s all got potential for causing an allergy.

Learn what nasal polyps are and their causes and treatments.

Are You at Risk?

The Allergy & Sinus Symptom Evaluator will assess your symptoms, treatments, and medical history.

You can blame heredity, but it’s not that simple. Read on to learn more.


Take steps to identify and avoid your allergy triggers and find out how to prevent a serious reaction. Click here.

Find out when it's OK to use a neti pot or other forms of nasal irrigation, and when you may need more help.


Asthma attacks (worsening of asthma symptoms) can be triggered by allergies, which can temporarily increase the inflammation of the airways in a susceptible person.

Many of us know the misery of allergies all too well -- the sneezing, runny nose, and postnasal drip; watery, itchy eyes, ears, nose, and throat. Whether from the symptoms or the medication we use to treat them, our sleep often suffers.

Sinusitis is an inflammation, or swelling, of the tissue lining the sinuses. Normally, sinuses are filled with air, but when sinuses become blocked and filled with fluid, germs (bacteria, viruses, and fungi) can grow and cause an infection.

Sometimes, allergies can cause a life-threatening reaction called anaphylaxis. It's not common, but you should be aware of what to do if it happens.

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