Sinus disease, also known as sinusitis or rhinosinusitis, is an inflammation of the sinuses and the nose. Sinuses are hollow spaces in the bones between your eyes, behind your cheekbones, and in your forehead, which are normally filled with air. When they become blocked and filled with fluid, germs can grow and cause an infection. Sinusitis can be caused by a variety of conditions, including viral infections, bacterial infections, allergies, and nasal polyps. The condition can be acute, subacute, chronic, or recurrent. Acute sinusitis is an inflammation of the cavities around your nasal passages (sinuses) caused by a variety of infections, including the common cold, a bad viral upper respiratory infection (URI) or bacteria. Chronic sinusitis is when that inflammation continues for more than three months and can be caused by a variety of conditions or is associated with allergies, asthma or nasal polyps. The symptoms of sinusitis include facial pain, a stuffy or runny nose, fever, and other symptoms. Chronic sinusitis can cause thick, discolored mucus from the nose, pain, tenderness, and swelling around the eyes, cheeks, nose, or forehead, and reduced sense of smell and taste. Treatment for sinusitis depends on the type of sinusitis diagnosed and can include over-the-counter products, prescription medications, and in some cases, surgery.