Healthwise

Sinusitis is an infection of the sinuses. It often starts when some kind of irritation or inflammation—like a cold, allergy, smoking, or pollution—causes the channels that drain the sinuses to swell and become blocked, making it hard to clear mucus. This fluid can then become infected, leading to congestion, pain, and pressure.

If someone gets frequent sinus infections, they may have chronic sinusitis. In these cases, your physician may want to examine your nasal and sinus cavities with an endoscope and take samples of any pus draining from the sinuses. Possible treatments could include antibiotics, nasal saline flushes, and a topical nasal steroid. If those treatments aren't effective, surgery may be necessary to fix the problem.