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Allergies Health Center

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Allergic Rhinitis - What Happens

The first time you are exposed to an allergen in the air, your body's immune system may recognize the allergen as a foreign substance. Your body reacts by making antibodies against the allergen.

The next time you are exposed to the allergen, the antibodies react to it. This releases histamine and other chemicals that cause the symptoms of your allergy. This is called sensitization. Sensitization may occur early in life.

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Children who have allergic rhinitis may become allergic to many allergens, including dust mites, dander on cats and dogs, and tree and grass pollens.


Allergic rhinitis can affect your health if you don't treat it. If it lasts a long time, you may have complications such as sinusitis, plugged ears, and ear infections. Some people with allergic rhinitis have sleep apnea. Some have asthma, and researchers are looking at whether allergic rhinitis may lead to asthma.

Allergic rhinitis can also affect your quality of life. You may avoid seeing people, have problems sleeping, and feel tired or grumpy. You may have trouble with school or work.

    WebMD Medical Reference from Healthwise

    Last Updated: May 13, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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