Sinusitis | Causes & Risk Factors


What causes sinusitis?

Anything that causes swelling in your sinuses or keeps the cilia from moving mucus can cause sinusitis. This can occur because of changes in temperature or air pressure. Allergies can cause sinusitis. Using decongestant nasal sprays too much, smoking, swimming or diving can also increase your risk of getting sinusitis. Some people have growths called polyps (say: “pawl-ips”) that block their sinus passages and cause sinusitis.

When sinusitis is caused by a bacterial or viral infection, you get a sinus infection. Sinus infections sometimes occur after you’ve had a cold. The cold virus attacks the lining of your sinuses, causing them to swell and become narrow. Your body responds to the virus by producing more mucus, but it gets blocked in your swollen sinuses. This built-up mucus is a good place for bacteria to grow. The bacteria can cause a sinus infection.

Written by editorial staff

Reviewed/Updated: 04/14
Created: 09/00