What is sinusitis?

Sinusitis is an inflammation, or swelling, of the tissue lining the sinuses. The sinuses are four paired cavities (spaces) in the head. They are connected by narrow channels. The sinuses make thin mucus that drains out of the channels of the nose. This drainage helps keep the nose clean and free of bacteria. Normally filled with air, the sinuses can get blocked and filled with fluid. When that happens, bacteria can grow and cause an infection (bacterial sinusitis).

What are the different types of sinusitis?

There are two types of sinusitis:

  • Acute bacterial sinusitis: A sudden onset of cold symptoms such as runny nose, stuffy nose, and facial pain that does not go away after 10 days, or symptoms that seem to begin improving but return worse than the initial symptoms. It responds well to antibiotics and decongestants.
  • Chronic sinusitis: A condition defined by nasal congestion, drainage, facial pain/pressure, and decreased sense of smell for at least 12 weeks.

Who gets sinusitis?

A sinus infection can happen to anyone. However, those with nasal allergies, asthma, and a deviated septum are all more likely to get sinusitis. Smoking can also cause sinus problems.

How can I tell if I have a sinus infection, cold, or nasal allergy?

It can be difficult to tell the difference between a cold, allergies, and a sinus infection. The common cold typically builds, peaks, and slowly disappears. It lasts a few days to a week. A cold can transform into a sinus infection. A nasal allergy is an inflammation of the nose because of irritating particles (dust, pollen, dander). Symptoms of a nasal allergy can include sneezing, itchy nose and eyes, congestion, runny nose, and post nasal drip (mucus in the throat). Sinusitis and allergy symptoms can happen at the same time as a common cold.

If you are fighting off a cold and develop symptoms of a sinus infection or nasal allergy, see your healthcare provider. You will be asked to describe your symptoms and medical history.

What causes sinusitis?

Sinusitis can be caused by a virus, bacteria, or fungus that swells and blocks the sinuses. A few specific causes include:

  • The common cold
  • Nasal allergies
  • Seasonal allergies
  • Polyps (growths)
  • A deviated septum (the nose is shifted, causing a structural blockage)
  • A weak immune system

What are the symptoms of sinusitis?

Common symptoms of sinusitis include:

  • Post nasal drip (mucus drips down the throat)
  • Nasal discharge (thick yellow or green discharge from nose)
  • Stuffy nose
  • Facial pressure (particularly around the nose, eyes, and forehead)
  • Toothache
  • Headache
  • Cough
  • Tiredness
  • Ear pain
  • Fever

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