Sinusitis is infection or inflammation of the mucous membranes that line the sinuses.

When a mucous membrane gets inflamed, it swells. This can block the normal flow of fluid from the sinuses into the nose and throat. Bacteria and fungi (plural of fungus) are more likely to grow and cause an infection in sinuses that can't drain.

The main cause of sinusitis is a viral infection, usually a cold. Allergies or other problems also can block the nasal passages and lead to sinusitis.

There are two types of sinusitis: acute (short-term) and chronic (long-term). You may have chronic sinusitis if:

• You have had more than three sinus infections in 1 year that needed antibiotics to clear up, OR
• You have had a sinus infection for more than 12 weeks that antibiotics have not cleared up.

Surgery may be a good choice for some people who have chronic sinusitis.

Surgery helps the sinuses drain, preventing infections. The doctor usually makes the sinus openings bigger by removing:

• Infected, swollen, or damaged tissue.
• Bone, to make a wider opening to let mucus drain from the sinuses.
• Growths (polyps) inside the nose or sinuses.

There are two types of sinus surgery:

• Endoscopic surgery is the type that is done most often. The doctor puts a thin, lighted tool called an endoscope in the nose to remove small amounts of bone or tissue that block the sinus openings. The doctor also can remove polyps.
• Traditional surgery may be done for certain serious problems—such as pus in a sinus, infection of the facial bones, or a brain abscess. The doctor makes an opening into the sinus from inside the mouth or through the skin of the face.

Sometimes another problem inside the nose (such as a deviated septum) also needs to be fixed. This may be done during the same surgery.

After surgery, the doctor may prescribe:

• Antibiotics to help fight infection.
• Steroid nasal spray to reduce inflammation and help you heal.
• Pain medicine.

Very few people need surgery to treat sinusitis. But you may need surgery if ALL of these are true:

• Your doctor says that you have chronic sinusitis.
• You've followed what's called "maximum medical treatment" for 4 to 6 weeks. This means that you've taken medicines and followed home treatment for at least 4 to 6 weeks. This treatment includes antibiotics, a steroid nasal spray, and other prescription medicines.
• You've had a CT scan of your sinuses after the 4 to 6 weeks of treatment. It is very important to have the CT scan done after this treatment. Reducing the swelling and infection as much as possible lets your doctor see what could be causing your infections.
• The CT scan shows that something, such as nasal polyps, is keeping your sinuses from draining as they should.

You also may need surgery if:

• You have a sinus infection caused by a fungus. Infections caused by fungi cannot be cleared up with antibiotics.
• You have a serious problem such as an infection that spreads beyond your sinuses. This is rare.

Sinus surgery can:

• Help your sinuses drain, which can prevent sinus infections.
• Improve your sense of smell. (But in some cases, scarring from surgery could decrease your sense of smell.)

Endoscopic surgery improves symptoms for about 90 out of 100 people. About 10 out of 100 people find that it doesn't help them.^{footnote 1}

Surgery has the best chance of working if you use a steroid nasal spray and do home treatment after surgery to prevent future infections. You may need to use these treatments for a long time.

Sinus surgery can lead to minor or serious problems.

• A small number of people have minor problems, such as:
  • Scar tissue.
  • Bleeding.
  • Infection.
  • A hole in the tissue between the nostrils (nasal septum).
  • Bruising and swelling around the eyes.

• Serious but rare problems can include:
  • Heavy bleeding.
  • Injury to the eye area.
  • Inflammation of the tissue that covers the brain (meningitis).
  • Leakage of the fluid around the brain.
  • Brain injury.
• Scarring from surgery could decrease your sense of smell.
• The surgery might not work, so you could need a second surgery.

Most of the time, you can treat your sinus problem with home care and medicines.

Home treatment

• Drink plenty of fluids to help keep the mucus thin.
• Hold a warm, damp towel or a warm gel pack to your face for 5 to 10 minutes several times a day.
• Breathe warm, moist air from a steamy shower, a hot bath, or a sink filled with hot water. Avoid very cool, dry air. A humidifier can add moisture to the air in your home.
• Use saltwater nasal drops or washes to help keep your nasal passages open and to wash out mucus and bacteria. You can buy saline nose drops or saline nasal washes (such as a Neti Pot) at a pharmacy or grocery store, or you can make your own at home. People around age 8 and older may also find it helpful to gargle often with warm salt water.
• If you need to blow your nose, do it gently. Blowing your nose too hard may force thick mucus back into your sinuses. Keep both nostrils open when you blow your nose.

Medicines

• Take pain relievers, such as acetaminophen or ibuprofen, that you can buy without a prescription.
• Use a steroid nasal spray or decongestant nasal sprays or pills to reduce the swelling of the mucous membranes. If you use a nasal spray, do not use it longer than what the label says.
• Take antibiotics as directed, if your doctor prescribes them. Antibiotics can treat most short-term (acute) sinusitis when it is caused by bacteria.
• Use mucolytics (such as guaifenesin) to thin the mucus in your sinuses.

Be safe with medicines. Read and follow all instructions on the label. Some medicines may not be safe for young children or for people who have certain health problems. Do not give cough and cold medicines to a child younger than 6 unless your child's doctor has told you to.

Your doctor might advise you to have surgery if:

• You have many sinus infections that need treatment with antibiotics.
• Home treatment doesn't stop your pain and other symptoms.
• You've taken medicines and done home treatment for 4 to 6 weeks, and tests show that you have a sinus problem that surgery can fix.