Chronic sinusitis is a long-lasting inflammation of the sinuses, which are the air-filled spaces located in the skull around the nose. This condition can cause symptoms such as nasal congestion, facial pain, and a reduced sense of smell. It often occurs when the sinus openings become blocked, leading to mucus buildup and infection. The causes of chronic sinusitis can include allergies, nasal polyps, or structural issues in the nasal passages. Treatment options may involve medications like nasal corticosteroids or antibiotics, and in some cases, surgery may be necessary to improve sinus drainage. Managing allergies and avoiding irritants can also help prevent flare-ups.