Nasal Polyps

What nasal polyps are

Nasal polyps grow from the lining of the sinuses, mainly around the openings of the ethmoid sinuses between the eyes, and hang down into the nasal passages. They look like peeled grapes: glistening, gray-yellow and soft. They have few nerves, so they do not hurt when touched.

Most nasal polyps are part of chronic rhinosinusitis with nasal polyps, long-term inflammation of the nose and sinuses lasting 12 weeks or more. In most adults in Western countries this inflammation is "type 2", driven by eosinophils (a type of white blood cell) and the same immune signals involved in allergic asthma. See chronic sinusitis for the wider condition.

Symptoms of nasal polyps

• Blocked or stuffy nose on both sides, constant rather than coming and going.
• Reduced or lost sense of smell, and dulled taste.
• Runny nose and postnasal drip.
• Facial fullness or pressure. Significant pain is less common than in sinus infections.
• Snoring, mouth breathing and poor sleep.
• Frequent sinus infections.

Polyps on one side only are less typical and need checking to rule out other growths, including tumors.

Causes and risk factors

• Asthma: a large share of people with nasal polyps have asthma, and polyps make asthma harder to control.
• Aspirin-exacerbated respiratory disease (AERD): the triad of asthma, nasal polyps and reactions to aspirin and other NSAIDs. Polyps in AERD are often severe and recurrent.
• Allergic fungal sinusitis: an allergic reaction to fungi in the sinuses, often one-sided, with thick dark mucus.
• Cystic fibrosis: the main cause of polyps in children.
• Allergic rhinitis: may contribute, though allergy alone is not the main cause.
• Rare causes: eosinophilic granulomatosis with polyangiitis and primary ciliary dyskinesia.

Diagnosis

1. Nasal endoscopy: a thin camera passed into the nose in clinic, after a numbing spray. It shows the polyps and their extent.
2. CT scan of the sinuses: shows how much the sinuses are blocked and is needed before surgery.
3. Blood tests: eosinophil count and IgE help identify type 2 inflammation.
4. Allergy testing.
5. Smell testing.
6. Biopsy: if a polyp is one-sided, bleeding or unusual.
7. In children: a sweat test or genetic test for cystic fibrosis.

Nasal polyps treatment

Steroid sprays and rinses

Nasal steroid sprays (such as fluticasone or mometasone) used every day are the first-line treatment. They shrink polyps and improve breathing and smell, but only with long-term regular use. Aim the spray outward, away from the center of the nose, with the head tilted slightly forward. Daily saline rinses clear mucus and help the medicine reach the lining. Steroid rinses (a steroid added to a saline bottle) work better than sprays for some people, especially after surgery.

Steroid tablets

A short course of oral steroids shrinks polyps quickly and can restore smell for weeks. Because of side effects such as raised blood sugar, bone thinning and mood changes, courses are limited, usually to one or two a year.

Biologic medicines

For severe polyps that return despite sprays and surgery, injectable biologics target type 2 inflammation. Those approved for nasal polyps include dupilumab, omalizumab and mepolizumab, with others now becoming available. They shrink polyps, improve smell and reduce the need for surgery and steroid tablets. They are given every 2 to 4 weeks or less often, long-term.

Sinus surgery

Endoscopic sinus surgery removes polyps and opens the sinuses through the nostrils, with no external cuts. It improves breathing and smell and lets sprays reach the sinuses afterward. Polyps commonly return over years, especially in AERD, so continuing steroid sprays or rinses after surgery is essential. Steroid-releasing implants may be placed at surgery or in clinic.

AERD-specific treatment

Aspirin desensitization followed by daily aspirin, done under specialist supervision, reduces polyp regrowth in some people with AERD. Avoiding NSAIDs is otherwise essential.

Other measures

• Treat allergies and asthma well.
• Avoid smoking and smoky environments.
• Antibiotics only for clear bacterial infection; they do not shrink polyps.

Complications

• Long-term loss of smell, which can affect food enjoyment and safety (smoke, gas, spoiled food).
• Sleep-disordered breathing.
• Worse asthma control.
• Rarely, very large polyps widen the nose or press on the eye socket.

Frequently asked questions

Can nasal polyps go away on their own?

Rarely. Because they are caused by ongoing inflammation, they usually persist or grow without treatment. Daily steroid sprays often shrink them, and a short course of steroid tablets can make them disappear temporarily. Many people need long-term treatment to keep them under control.

What causes nasal polyps?

They are caused by long-term inflammation of the nose and sinus lining, usually chronic sinusitis. They are linked to asthma, aspirin-exacerbated respiratory disease, allergic fungal sinusitis and, in children, cystic fibrosis. The exact trigger for the inflammation is often unknown.

Are nasal polyps cancerous?

No. Nasal polyps are benign growths. However, a growth on only one side of the nose, especially with bleeding, pain, numbness or a loose tooth, needs examination and possibly a biopsy, because rare tumors can look similar.

Do nasal polyps come back after surgery?

Often, yes. Recurrence is common over several years, especially in people with asthma and aspirin sensitivity. Using steroid sprays or rinses every day after surgery, and biologic medicines for severe cases, greatly reduces the chance of regrowth.

Will I get my sense of smell back after nasal polyps treatment?

Many people do. Steroid tablets, surgery and biologics often improve smell, sometimes within days. But long-standing polyps can permanently damage the smell nerves in some people, so earlier treatment gives the best chance of recovery.