The nose and the sinuses are lined with a membrane that produces mucus.
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.
| Author | Amy Fackler, MA |
| Author | Debby Golonka, MPH |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman |
| Associate Editor | Terrina Vail |
| Primary Medical Reviewer | Renée M. Crichlow, MD - Family Medicine |
| Primary Medical Reviewer | Martin Gabica, MD - Family Medicine |
| Primary Medical Reviewer | Kathleen Romito, MD - Family Medicine |
| Specialist Medical Reviewer | Charles M. Myer, III, MD - Otolaryngology |
| Last Updated | August 22, 2006 |
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