Nasal polyps are soft, noncancerous growths that form in the nose or sinuses. They are usually pear-shaped and can range in size from microscopic to several centimeters.

Nasal polyps are often associated with allergies or asthma, and can be caused by long-term inflammation and swelling in the nose. The exact cause of nasal polyps is not fully understood, but research suggests that those affected may have an abnormal immune response. If you need treatment, you'll likely start with a nasal corticosteroid spray. Other treatments include taking corticosteroids by mouth, or getting a shot of dupilumab (Dupixent).