A nasal polyp is a mass of swollen, mucus-covered tissue that grows
out from the sinuses into the nasal passages inside the nose. One or more
polyps may appear at the same time and block the nasal passages, making it
difficult for a person to breathe and reducing the sense of smell.
Nasal polyps commonly develop in people who have chronic sinus
Small polyps can usually be treated with nasal sprays containing
corticosteroids. If polyps do not respond to treatment with a nasal spray, they
may need to be removed surgically. But even when treated successfully,
polyps frequently return.