A sinus infection (sinusitis) is a condition characterized by symptoms such as nasal congestion, facial pain, and thick, yellow-to-green mucus. It is most often caused by a virus; however, bacteria and fungi may occasionally play a role. Most cases get better on their own within 7 to 10 days. When necessary, treatment may include things such as decongestants, nasal irrigation, pain relievers, or antibiotics.
Sinusitis (also known as a sinus infection) is a medical term used to describe inflammation (swelling and irritation) of the paranasal sinuses. Because many cases of sinusitis are caused by an infection, you may hear the terms "sinus infection" and "sinusitis" used interchangeably.
The paranasal sinuses are hollow air spaces located within the skull. They include the frontal, maxillary, ethmoid, and sphenoid sinuses. These sinuses connect to the nasal passages through an opening that allows movement of air and mucus in between the nose and sinuses.
There are two main types of sinus infections: acute and chronic. An acute sinus infection is diagnosed when symptoms have lasted no longer than four weeks. A chronic sinus infection is diagnosed when symptoms have lasted for at least 12 weeks, despite medical treatment. Sinus infections may also be classified as subacute or recurrent.
(Click Sinusitis Types to learn more.)