What Are Nasal Polyps? Symptoms, Causes, Diagnosis, Treatment, and Prevention

In simple terms, nasal polyps are unhealthy sinus tissue growths inside the nose, says Jean Kim, MD, PhD, an associate professor of otolaryngology at Johns Hopkins Medicine in Baltimore. “By ‘unhealthy,’ I mean full of inflammation — tissues and cells behaving badly,” Dr. Kim says.

Nasal polyps are a subgroup of chronic rhinosinusitis (CRS), which affects about 1 in 8 adults. CRS is characterized by inflammation of the nose and sinus cavities. About 20 percent of people with CRS have nasal polyps, which are benign growths in the nasal cavities that are thought to originate in the ethmoid sinuses (the hollow spaces in the bones around the nose).

These soft, painless, noncancerous growths develop in the lining of the nasal passages or sinuses; they typically form in clusters and hang down in the shape of a teardrop or tiny grape.

The symptoms of nasal polyps can have a significant impact on quality of life, says Kim. “One of the most common symptoms is the sensation of congestion and nasal obstruction,” she says.

Prolonged inflammation of the lining of the nose and sinuses, also called CRS, is associated with nasal polyps, but it’s not completely clear what causes it, says Kim. “The membranes become inflamed, which can include swelling, redness, and fluid buildup. This can continue for a long time or happen over and over again,” she says.

Tissue samples taken from nasal polyps have led some experts to believe that allergies and infections cause the inflammation.

Those samples contained extra eosinophils, which are white blood cells linked to infections and allergic reactions. The resulting inflammation causes small growths filled with fluid that eventually turn into polyps.

Genetics

There is some evidence that genetics may influence the likelihood that a person will develop nasal polyps, says Kim.

A study found that the prevalence of nasal polyps among relatives was nearly five times that of the control group, leading the authors to conclude the results “strongly indicate that heredity is important in the development of nasal polyps.”

The exact genetic component that may increase the risk of nasal polyps hasn’t been established, but it appears that it may involve the genes that play a role in the immune system and inflammatory response. One study noted that a specific single nucleotide polymorphism (a common type of genetic variation) seemed to be associated with an increased risk of nasal polyps.

Asthma and Allergies

“In the United States, the greatest risk factor is having a condition such as asthma, allergies, or eczema; those people will tend to be at greater risk for developing nasal polyps,” says Kim.

Other risk factors for nasal polyps include the following.

Sensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) or aspirin
Allergic fungal sinusitis
Cystic fibrosis
Churg Strauss syndrome
Vitamin D deficiency

Exposure to Irritants

Textile workers who have been exposed to occupational dust, particularly those who have had long-term exposure, appear to have an increased prevalence of nasal polyps.

After a complete health history and physical exam, your healthcare provider will examine your nose with an otoscope or a simple lighted tool. In some cases, they may be able to see your polyps, but not always.
Your primary care doctor may be able to further explore what’s triggering the growth of your polyps through testing, or they may refer you to an otolaryngologist, also known as an ear, nose, and throat doctor (ENT), or an allergist.

Tests for nasal polyps can include the following:

Nasal Endoscopy In this procedure, a long, flexible tube with a light on the end is inserted into your nose. This allows the doctor to have a comprehensive view of your inner nose and your sinuses.
Computed Tomography (CT) Scan To aid in the full evaluation of the sinuses, a CT scan may be performed. For this diagnostic test, X-rays are used to create images of structures inside the body that can be analyzed by a radiologist with a computer.
Magnetic Resonance Imaging (MRI) If needed, an MRI scan can help a doctor evaluate for any complications of polyps as well as rule out other conditions that can look like polyps. An MRI machine uses a magnetic field to make images of inner organs and other structures.
Allergy Testing Allergies can contribute to the likelihood of nasal polyps.

Polyps typically occur in both nasal passages. Polyps that occur on only one side may indicate a benign or cancerous tumor, especially if there is also bloodstained nasal discharge. In that case, a polyp biopsy may be performed to rule out a cancerous growth.

Steroids, biologic drugs, and surgery are among the possible treatments for nasal polyps.
In some cases, dietary supplements may relieve the symptoms caused by polyps, but be sure to clear it with your doctor before trying any new supplements.

Medication Options

Treatment for nasal polyps generally starts with drug therapy.

Nasal Corticosteroids If the polyps are very small, they may be treated with nasal steroids, says Kim. Nasal steroids may be in the form of sprays, drops, or an additive to nasal saline irrigations. Options include:

fluticasone nasal (Flonase)
budesonide nasal (Rhinocort)
mometasone nasal (Nasonex)
triamcinolone nasal (Nasacort)
beclomethasone nasal (Qnasl)
ciclesonide nasal (Omnaris)

Oral Steroids If the polyps are big or you have a large disease load, oral corticosteroids like prednisone (Deltasone) may be prescribed. “We try to avoid using these because they can have serious and potentially harmful side effects,” says Kim.

Injectable Corticosteroids Injectable steroids may be used if the polyp load is severe.

Biologic Drugs Monoclonal antibodies can be used to treat nasal polyps and can work well for some patients, says Kim. Three biologics have come onto the market since 2019: mepolizumab (Nucala), dupilumab (Dupixent), and omalizumab (Xolair).
Biologic drugs are still relatively new medications, and their long-term effects are still unclear.

“Although these drugs can be expensive, they are a good option to try; they can potentially treat the polyps so that surgery is unnecessary,” Kim says.

Antihistamines or Antibiotics If allergies or chronic or recurrent infections appear to be causing swelling in your nasal passages or sinuses, your doctor may prescribe antihistamines or antibiotics to treat the underlying cause.

Aspirin Desensitization Some people with nasal polyps have aspirin sensitivity and may benefit from aspirin desensitization, in which very small doses of aspirin are administered and gradually increased as the person becomes able to tolerate them. This is usually done under the supervision of an allergy specialist.

Surgical Options

For people whose symptoms aren’t controlled by medication, surgery is an option. But surgery may not be a permanent solution: Rates of relapse and repeated intervention are high. The goal of surgery is not only polyp removal but also opening the sinuses to improve access for topical steroid therapies following surgery.

Endoscopic Surgery In endoscopic surgery, a small tube with a lighted magnifying lens or tiny camera is inserted into your nostrils so that the surgeon can access your sinus cavities and remove the polyps. It’s usually performed as an outpatient procedure.

In the most severe cases, both surgery and aggressive medical therapy, including biologics and delivery of steroids via nasal irrigation, may be necessary to treat the polyps, says Kim.

Alternative and Complementary Therapies

Some research has found that some supplements may minimize inflammation, which in turn can help with the symptoms of polyps. For example, one study that involved a randomized controlled trial found that supplementing with omega-3 fatty acids (fish oil) helped delay the recurrence of nasal polyps following treatment with steroids.

Supplements may have side effects or interact with medications you are taking, so you should discuss any supplements you are considering with your healthcare provider.

Bromelain There is some evidence that bromelain, an enzyme derived from pineapples, may reduce inflammation and swelling and relieve symptoms of sinusitis.
Bromelain may increase the risk of bleeding, so people who take blood thinners should not take bromelain without talking to their doctor first.
Taking bromelain with ACE inhibitors may cause blood pressure to drop.

Quercetin Quercetin is a flavonoid that has been shown to inhibit the production and release of histamine in lab studies. Histamine causes allergy symptoms such as a runny nose and watery eyes. But more studies are needed to confirm that it has the same effect in humans.

Sinupret This herbal combination is produced in Europe and imported into the United States. Sinupret contains Sambucus nigra (European elder), Rumex acetosa (common sorrel), Primula veris (cowslip), Verbena officinalis (European vervain), and Gentiana lutea (gentian). The herbs it contains may work by thinning mucus and helping the sinuses drain, which can relieve some of the symptoms of sinusitis.

In a review of existing literature on various alternative and complementary therapies for chronic rhinosinusitis and chronic rhinosinusitis with nasal polyps, in which studies involving baby shampoo, honey, capsaicin, therapeutic ultrasonography, phonophoresis, phototherapy, and acupuncture were investigated, the authors concluded that there wasn’t enough evidence to recommend any of the treatments for widespread use.

Although there isn’t a drug or lifestyle change that can prevent nasal polyps, there are a few strategies that may reduce your chances of developing them or having a recurrence after treatment, including:

Medical management of allergies and asthma
Avoidance of nasal irritants such as dust, air pollution, and smoke
Good hand hygiene
Humidifier use

Neti Pot or Nasal Rinse A neti pot is a little teapot with a long spout that can be used to flush out nasal passages with saline solution to improve mucus flow and remove allergens and irritants. If you do use a neti pot, be sure to use distilled, sterile, or previously boiled water. Tap water isn’t safe to use because it contains low levels of bacteria and protozoa, including amoebas.

The prognosis for nasal polyps can vary widely from case to case, says Kim. The likelihood that polyps will recur after treatment may depend on the underlying condition that led to the polyps in the first place.
It can also depend on how regularly an individual with polyps uses prescribed treatments and practices recommended self-care protocols.

“As far as we know, we do not have a drug that will take nasal polyps away permanently,” says Kim. If you find a medication that works to treat your nasal polyps, you will have to stay on that medication, or the polyps will come back, she says.

“If your nasal polyps get to a phase in which you have a very large and significant polyp load, it’s very hard to get them to go away,” she says.

Though they can negatively impact quality of life and make breathing more difficult, there isn’t evidence that nasal polyps increase the risk of death.

Nasal polyps can cause additional health problems that are important to know about.

Obstructive Sleep Apnea People with chronic rhinosinusitis who also have nasal polyps often have sleep disruption and sleep apnea. In some cases, larger polyps can fill 75 to 90 percent of the nasal cavity, which can lead to mouth breathing and snoring and possibly result in sleep apnea.
Asthma Flare-Ups If a person has really severe nasal polyp disease, it can impact their breathing and sometimes worsen asthma for a person who has asthma, says Kim.
Sinus Infections Sinus infections are a common complication of nasal polyps.
Other Infections In rare cases, nasal polyps can lead to more serious infections, including infection of the tissue around the brain and spinal cord (meningitis), infection around the tissue of the eye, or infection of the sinus bones.

Nasal polyps can develop in anyone, and they are common. It’s estimated that about 4 percent of Americans (13 million) have them. Men are more prone to nasal polyps than women, although women seem to have more-severe cases.

It’s rare that someone has nasal polyps before the age of 30. If a child develops nasal polyps, they should be evaluated for cystic fibrosis. Nasal polyps are present in up to 86 percent of people with cystic fibrosis.

More research is needed to determine if nasal polyps are more prevalent or severe in people of different races and ethnicities than in white Americans. Lower rates of surgery for nasal polyps have been reported in Black and Hispanic populations, but this may be due to lack of access to care or failure to seek care rather than lower prevalence.

Asthma is a risk factor for nasal polyps, and Black Americans are disproportionately impacted by asthma. In 2023, Black Americans were 30 percent more likely to have asthma than white Americans.

Nasal polyps are associated with a number of other medical conditions, including these.

Allergic Fungal Rhinosinusitis (AFRS) AFRS is a particular type of chronic rhinosinusitis that occurs because of an allergic response to inhaled fungi in a predisposed individual with nasal polyps. It tends to occur more often in the southern United States and along the Mississippi River Basin.

Asthma In people with asthma, the airways in the lungs can become inflamed and narrowed during an attack, which can make it harder to breathe. This chronic condition often begins in childhood; about 1 in 13 people in the United States have asthma.

Cystic Fibrosis (CF) Cystic fibrosis is a genetic condition that impacts the body’s cells, tissues, and glands that make mucus and sweat. People with CF have thick, sticky mucus that can build up in the body and cause blockages and infections.

Samter’s Triad Also known as aspirin-exacerbated respiratory disease (AERD), Samter’s triad is a nonallergic hypersensitivity reaction in which people have three conditions: asthma, aspirin allergy, and nasal polyps. It occurs in less than 1 percent of the general public and typically develops between ages 29 and 34.