Allergies Health Center

Nasal Polyps

Nasal polyps are common, noncancerous, teardrop-shaped growths that form in the nose or sinuses, usually around the area where the sinuses open into the nasal cavity. Mature nasal polyps look like seedless, peeled grapes.

Often associated with allergies or asthma, nasal polyps may cause no symptoms, especially if they're small, and require no treatment. But larger nasal polyps can block normal drainage from the sinuses. When too much mucus accumulates in the sinuses, it can become infected, which accounts for the thick, discolored drainage in the nose and throat that affects many people with nasal polyps.

Nasal polyps shouldn't be confused with the polyps that form in the colon or bladder. Unlike these types of polyps, they're rarely malignant. Usually, they're thought to result from chronic inflammation or a family tendency to develop nasal polyps.

Nor should nasal polyps be confused with swollen turbinates, which are the normal tissue that lines the side of the nose. Unlike swollen turbinates, they're not painful to the touch.

In most cases, nasal polyps respond to treatment with medications or surgery. Because they can recur after successful treatment, however, continued medical therapy is often necessary.

Symptoms of Nasal Polyps

Symptoms of nasal polyps include:

• nasal obstruction
• nasal congestion
• sneezing
• postnasal drip
• runny nose
• facial pain
• reduced ability to smell (hyposmia)
• loss of smell (anosmia)
• loss of taste
• itching around the eyes
• chronic infections

Most people with nasal polyps have runny nose, sneezing, and postnasal drip; about 75% have a decreased sense of smell. Many people also develop asthmatic symptoms such as wheezing, sinus infections, and sensitivity to fumes, odors, dusts, and chemicals. Less commonly, people with nasal polyps also have a severe allergy to aspirin and reaction to yellow dyes.

If you have nasal polyps, you have an increased risk of chronic sinusitis. When nasal polyps become particularly large, they can push the nasal bones apart and broaden the nasal bridge, which can adversely affect appearance and self-esteem.

If you have severe allergy to aspirin or yellow dyes, you should consult your doctor for evaluation of nasal polyps. In people with a combination of aspirin allergy, yellow dye sensitivity, and nasal polyps, allergic reaction is potentially life threatening.

Risk Factors for Nasal Polyps

Nasal polyps can affect people of any age, but they're most common in adults over age 40, and are twice as likely to affect men as women. They rarely affect children under age 10. When young children develop nasal polyps, cystic fibrosis should be considered as a possible diagnosis.

Although nasal polyps are associated with allergic rhinitis, asthma, aspirin allergy, sinus infections, acute and chronic infections, a foreign body in the nose, and cystic fibrosis, many times the cause is unknown. Sometimes, the formation of nasal polyps precedes the development of asthma or sinusitis.

Some researchers theorize that symptoms of allergies -- including runny nose, sneezing, and itching -- predispose people to develop nasal polyps. But the allergy connection is controversial. Some research suggests that nasal polyps may develop in nearly one-third of patients with asthma but only in about 2% of patients who have seasonal allergies with no diagnosis of asthma. Other researchers theorize that sinus infections -- which cause tissue swelling and diminished drainage -- lead to the formation of nasal polyps.