Nasal polyps are swellings of the normal nasal lining that occur inside the nasal passages and sinuses (air-filled spaces behind the nose, eyes and cheeks).
They are typically pearly in colour and can vary in size. Each polyp is teardrop-shaped, and can look like a grape when fully grown.
You may not always know if you have nasal polyps because they can be difficult to see and don't always cause any symptoms.
What problems can they cause?
Nasal polyps usually only cause problems if they are large or grow in clusters.
Symptoms can include:
a blocked nose, which can make it difficult to breathe through your nose
a runny nose
mucus that drips from the back of your nose down your throat (post-nasal drip)
a reduced sense of smell or taste
a feeling of fullness or pressure in the face
obstructive sleep apnoea (OSA) – your airways become temporarily blocked while you're asleep, which can disturb your sleep
If polyps block your sinuses, they can cause a build-up of fluid that may become infected (sinusitis). If this happens, you may have facial pain,toothache and a high temperature (fever).
When to see your GP
The symptoms of nasal polyps can be very similar to those of more common conditions, such as a cold. However, colds tend to clear up within a few days, whereas nasal polyps usually won't get better unless they're treated.
You should see your GP if you have nasal symptoms that last a month or more.
What causes nasal polyps?
Nasal polyps are thought to develop as a result of inflammation of the lining of the nasal passages and sinuses. The lining becomes increasingly swollen and then hangs down.
It's unclear exactly what triggers this inflammation, although certain things can increase your risk of developing nasal polyps, including:
asthma– 20-40% of people with nasal polyps also have asthma
aspirin intolerance – allergy-like symptoms, such as a watery nose, occur if you take aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen
Nasal polyps usually affect adults and are more common in men than women. They're rare in children.
Diagnosing nasal polyps
Your GP will ask you about your symptoms and examine the inside of your nose.
Further tests carried out at the ear, nose and throat (ENT) department of your local hospital will often be needed to confirm polyps and to determine how large they are and how many you have.
This will usually involve an endoscopy (where a small tube with a camera at one end is inserted up your nostril) or a computerised tomography (CT) scan.
Treating nasal polyps
Nasal polyps can be difficult to get rid of permanently, but steroid medication can often help shrink them, and surgery to remove them can be carried out if medication doesn't help.
The main treatments are:
corticosteroid nose drops or nasal sprays to shrink the polyps over a number of weeks or months
corticosteroid tablets to shrink larger or more troublesome polyps quickly, although they're not usually used for more than 10 days because of the risk of side effects
surgery to remove large or persistent polyps using tiny surgical instruments inserted up your nostrils
As polyps can grow back after treatment, including after surgery, you will usually be advised to continue using corticosteroid nasal sprays to help stop them returning quickly.
Treating nasal polyps
Nasal polyps can be difficult to get rid of permanently, but steroid medication can often help shrink them, and surgery can be carried out to remove them if medication doesn't help.
Steroid sprays and drops
Your GP or specialist may initially prescribe nose drops or a nasal spray that contains steroid medicine (corticosteroids). These can reduce inflammation in your nose and help shrink your polyps.
Steroid nose drops may be recommended first because these generally work faster than sprays. However, they are usually only prescribed for around two weeks because they can cause side effects.
Common side effects include:
irritation of the inside of the nose
If your symptoms improve while taking the drops, long-term treatment with a steroid nasal spray will usually be recommended to reduce the chances of the polyps returning quickly.
Speak to your GP or specialist if your symptoms don't improve while using a steroid spray or nose drops. You may require additional treatment with steroid tablets.
If you have large polyps, or you still have symptoms after using steroids drops or sprays, a short course of steroid tablets (oral corticosteroids) may be recommended in combination with nose drops.
A medication called prednisolone is usually used. It's likely you will be prescribed no more than 5 to 10 days' worth as using it for longer than this increases your risk of developing side effects such as:
weakening of your bones (osteoporosis)
high blood pressure
If your symptoms do not improve after taking steroid tablets, your doctor may suggest having surgery to remove your polyps. If they do get better, long-term treatment with a steroid nasal spray will usually be recommended.
Surgery to remove nasal polyps may be recommended if steroid medication doesn't help or your polyps are particularly large.
The procedure to remove nasal polyps is called endoscopic sinus surgery. It's carried out under general anaesthetic, sometimes as a day procedure.
The surgeon will pass an endoscope (a tube with a video camera at one end) into your nostrils to allow them to see inside your nose and sinuses.
Surgical instruments, such as a micro-debrider (a tiny motorised revolving shaver) are passed up your nostrils and used to remove the polyps. This means it's not necessary to make any cuts to your face.
After surgery, you will be observed for a few hours. If a dressing has been used, it will be removed from your nose after this time. If there is no bleeding, you will be discharged and allowed home to continue your recovery.
You will usually be advised to rest for around two weeks after surgery. Your surgeon will be able to give you more detailed information and advice.
Common problems that occur after endoscopic sinus surgery include:
crusting inside the nose, which will usually get better in a few weeks
persistent nosebleeds, which may require further surgery
an infection at the site of the surgery, which can usually be treated with antibiotics
Most people who have endoscopic sinus surgery will experience an improvement in their symptoms. However, it's common for polyps to grow back – usually within a few years – and treatment may need to be repeated regularly.
Long-term use of steroid nasal spray will usually be recommended after surgery to help stop polyps returning quickly.