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Allergies Health Center

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Sinusitis and Mucous Membrane - Topic Overview

The nose and the sinuses are lined with a membrane that produces mucus.

  • When air enters the nose, it is warmed, moistened, and filtered before passing into the lungs.
  • Dust, smoke, bacteria, and other irritants often become trapped in the mucus that lines the nasal passages.
  • This mucus is pushed to the back of the throat by tiny hairs (cilia) that line the inside of the sinuses and nose, and the mucus is eventually swallowed.

If the mucous membrane becomes inflamed, it may swell, blocking the openings that drain the sinuses. Mucus inside the sinuses then becomes trapped. Both the inflammation and the pressure of trapped mucus cause pain. Also, bacteria trapped in the mucus can grow, causing a bacterial sinus infection.

Recommended Related to Allergies

Relief for Allergies at Home

Your home is your castle -- except when you’re allergic to it. A recent nationwide survey found that over half of all Americans test positive for at least some allergens, and many of these are indoor allergies such as dust, mold, and pet dander. How can you allergy-proof your home to make it a refuge, not a source of sneezes? Take a tour of your house from room to room, find out where the allergens are lurking, and get relief from indoor allergies.

Read the Relief for Allergies at Home article > >

    WebMD Medical Reference from Healthwise

    Last Updated: November 14, 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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