A sinus infection, also called sinusitis, is a common condition that causes inflammation and swelling of the sinuses. The sinuses are air-filled cavities located in the skull around the nose and eyes. When the sinuses become infected, they can fill with fluid and mucus, causing pain, pressure, and congestion.
Sinus infections can be caused by a variety of factors, including allergies, colds, and the flu. They can also be caused by bacteria or fungi. Symptoms of a sinus infection can include facial pain and pressure, headache, congestion, runny nose, and fever. Sinus infections can be treated with antibiotics, decongestants, and pain relievers.