Sinus Infection Overview

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Sinus infection, also known as sinusitis, is an inflammation of the sinuses and is usually caused by a viral, bacterial, or fungal infection. Sinuses are the air-filled cavities behind the forehead, cheeks, and eyes that are lined with mucous. When the sinuses are inflamed, mucous does not drain as usual and can become infected with bacteria or other organisms.

There are four kinds of sinus infection: acute, subacute, chronic, and recurrent. The most common is acute, which is an uncomfortable condition that lasts 4 weeks or less. However, if left untreated, an acute sinus infection can become subacute (lasting 4 to 8 weeks) or chronic (lasting 8 weeks or more). Recurrent sinus infections are several acute attacks within a year that result for different reasons. In rare cases, sinus infection can result in brain infection and other serious complications, so it's important to talk to your health care provider about your symptoms as soon as possible.

What are Sinuses?
In rare cases, sinus infection can result in brain infection and other serious complications, so it's important to talk to your health care provider about your symptoms as soon as possible.

Frontal - over the eyes in the brow area.

Maxillary - inside each cheekbone.

Ethmoid - just behind the bridge of the nose and between the eyes.

Sphenoid - behind the ethmoids in the upper region of the nose and behind the eyes.

People most at risk to develop a sinus infection are those who have a disease that prevents the cilia (small hairs) from working properly such as cystic fibrosis, or those who have a weakened immune system due to HIV or chemotherapy.

Others at risk for developing sinus infection are those who:

• Have asthma.
• Overuse nasal decongestants (the problem gets worse when these are used too often or too long).
• Have a deviated nasal septum, nasal bone spur, or polyp.
• Have a deviated nasal septum, nasal bone spur, or polyp.
• Swim or dive frequently.
• Had recent dental work.
• Are pregnant.
• Are exposed to changes in altitude (flying or scuba diving).
• Exposed to air pollution and smoke.
• Exposed to air pollution and smoke.
• Are hospitalized, especially for a head injury or have had a tube placed into their nose.