What is sinusitis?

Sinusitis is a common thing. Acute sinusitis is not very uncommon after an upper respiratory infection, such as a bad cold. It's that dull throbbing pain you feel in your eyes or beneath your cheekbones. It's worse when you bend over or your head is down, and in most cases, it goes away without specific treatment as you get over the cold. When there's chronic sinusitis, other kinds of treatments may be required. In rare cases, surgery is required to drain the sinuses.
Sinusitis is the inflammation of the sinus cavity. A person's nasal passageway becomes swollen, causing pain, nasal congestion, headaches, and tenderness. The ability to smell and taste may be affected. A doctor's diagnosis is usually based upon these symptoms. Sinusitis can be caused by infection (bacterial or viral), allergies, or other problems, and may be acute (lasting up to 4 weeks), subacute (4 to 12 weeks), or chronic (12 weeks or longer). Sometimes an x-ray is performed as well as other imaging tests to confirm the diagnosis. Your doctor may prescribe antibiotics to treat infection if bacterial infection is suspected, but antibiotics will not treat a viral infection.

Sinus infection (sinusitis) is an inflammation of the mucous membranes that line the sinus cavities.  This inflammation causes the mucous glands in the sinuses to secrete more mucus.  When the passages in the sinuses become blocked, pressure develops, and the nose may feel plugged. Sinusitis can be caused by a virus, allergic rhinitis (hay fever), chronic rhinitis, deviated nasal septum or polyps, and may run in families. Irritants, air pollution, smoke, and fumes may also cause inflammation and lead to bacterial growth and infection.

Acute sinusitis is generally caused by a bacterial infection. Chronic sinusitis may not be associated with infection but may be due to other problems as mentioned above.  Symptoms may also occur which do not respond to medical treatment.

Chronic sinusitis may produce fewer symptoms such as chronic sore throat and cough, particularly when reclining, decreased sense of smell, bad breath, nasal congestion, and a low grade fever (less than 101 degrees F).  In chronic sinusitis, the symptoms are often more subtle.  Some people just have drainage, sore throat, or a cough that lasts for days to weeks.

Audrey K. Chun, MD
Geriatric Medicine
The sinuses are hollow spaces in the bone of the skull that connect to the nasal airway -- they occur in the cheeks, at each side of the bridge of the nose, in the forehead and in the middle of the head a couple of inches back from the nasal bridge. The spaces are lined with a membrane containing cells that secrete mucus, which filters and warms the air you breathe in. If you've had a respiratory infection, such as a cold, the membrane can become thickened and inflamed, preventing the mucus from draining. As the mucus builds up, bacteria can take hold, resulting in a sinus infection. The symptoms include painful pressure at the front of the face and brow (you also may notice swelling), thick yellow or green nasal discharge, and nasal congestion. Sinusitis also can cause sensitivity or pain in the upper teeth.
The sinuses are air-filled spaces above, between, and beneath your eyes, flanking your nose. Both the nose and sinuses are lined with a thin membrane that swells and produces mucus in response to irritation. Normally, the mucus from the sinuses drains through small openings, known as ostia, which connect the sinuses to the nasal passages.

Sinusitis is a common condition in which the sinuses—the four cavities around the nasal passages—become inflamed and swollen. This causes mucus buildup that makes it difficult to breathe through your nose. Sinusitis can be acute (lasting up to 4 weeks), sub-acute (lasting from 4 to 12 weeks), or chronic (lasting 12 weeks or longer despite treatment). Besides difficulty breathing, the condition can cause pain and swelling around your eyes, nose, cheeks, and forehead, and a throbbing headache.

Approximately 30 million Americans (one in seven) suffer from acute sinusitis each year. Some experience several bouts a year, and many have a chronic problem. Sinusitis is more common in adults than children.

Rick C. Jensen, MD
Ear, Nose & Throat (Otolaryngology)
A simple cold can cause sinusitis and set off a cascade of problems. In this video, Dr. Rick Jensen describes what sinusitis is and when to seek treatment.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.