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Last full review/revision Sep 2020| Content last modified Sep 2020
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What is sinusitis?

Your sinuses are hollow spaces behind your cheeks and forehead. Each sinus opens into your nose. Sinusitis is inflammation or an infection in one or more of your sinuses.

Locating the Sinuses

Locating the Sinuses

What causes sinusitis?

Sinusitis is usually caused by a:

  • Viral upper respiratory infection (such as a cold)

The viral infection makes the tissue inside your nose swell. That's why your nose is stuffy when you get a cold. The swelling in your nose blocks the openings to your sinuses, which causes fluid to build up in the sinuses. Allergies Seasonal Allergy An allergy is when your body's immune system reacts to something harmless, such as food, plants, or medicine. Seasonal allergies are allergies that happen only during the time of year when a... read more also make the inside of your nose swell and can cause sinusitis.

Sometimes, bacteria get into the sinus fluid and cause:

  • Bacterial sinusitis

Chronic sinusitis is more common if you have:

What are the symptoms of sinusitis?

Symptoms include:

  • Yellow or green pus (thick fluid) from your nose

  • Pressure and pain in your face

  • Stuffy nose

  • Bad breath

  • Coughing up mucus, especially at night

  • Sometimes, feeling ill all over, fever, and chills

Go to a doctor right away if you have these symptoms and also a severe headache and are confused because the infection could have spread to your brain (meningitis).

How can doctors tell if I have sinusitis?

Doctors can tell based on your symptoms and an exam. Sometimes, doctors do:

  • CT scan to see if the infection is spreading or if you have chronic sinusitis

  • Endoscopy (putting a thin tube with a microscope in your nose to look at your sinuses)

How do doctors treat sinusitis?

Doctors treat sinusitis by helping your sinuses drain. Doctors will tell you to:

  • Breathe in steam from a hot shower

  • Put hot, wet towels on your face (over your sinuses)

  • Drink hot fluids

  • Flush a saltwater solution through your nose or use a salt-water spray

  • Use a nasal decongestant spray, such as phenylephrine

If you have a fever, severe pain, or sinusitis that lasts for more than 10 days, doctors usually prescribe antibiotics.

If you have chronic sinusitis (sinusitis that lasts more than 90 days), doctors may:

  • Have you take antibiotics for 4 to 6 weeks

  • Do surgery to wash out your sinuses and help them drain

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