Nasal polyps are usually pearly grey in colour and they vary in size. Each polyp is a soft teardrop-shaped swelling which hangs down, resembling a small grape within the nose. Nasal polyps are difficult to see and they may not cause any symptoms, so many people don’t realise they have them.
Nasal polyps will usually only cause a problem if they become large or grow in clusters. In these cases, nasal polyps can cause discharge or infection within the nasal passage or sinuses (the air-filled spaces behind the nose, eyes and cheeks). This may cause a blockage resulting in a fluid build-up in your sinuses (sinusitis) which may be painful.
The exact cause of nasal polyps is not known. They may develop as a result of inflammation of the sinuses and the nasal passages causing the lining to swell and hang down. The underlying cause of this inflammation may not be known, but it is thought that your risk of developing nasal polyps increases if you have:
- asthma (a high proportion of people with nasal polyps also have asthma)
- aspirin intolerance (allergy-like symptoms)
- having a family history of nasal polyps
Nasal polyps are rare in children and affect more men than women.
The symptoms of nasal polyps include a blocked or runny nose, mucus dripping from the back of the nose down your throat and a reduced sense of smell or taste.
Symptoms can be very similar to those of a number of other more common conditions, such as flu or a common cold. However, unlike these conditions, the symptoms of nasal polyps don’t usually get better without treatment.
You should see your doctor if you suspect you have nasal polyps or if you have nasal symptoms lasting for a month or more. These can include a blocked nose which means it’s difficult to breathe through your nose. You may have a runny nose or have mucus that runs down your throat out of the back of your nose (post-nasal drip). Your sense of taste and smell may be reduced, and you may feel a pressure or fullness across your face. You may snore or suffer from obstructive sleep apnoea (OSA) which is repetitive pauses in your breathing while you’re asleep. If nasal polyps cause your sinuses to become blocked, this might lead to infection (sinusitis) which can cause facial pain, toothache or a fever.
Symptoms can include:
- blocked nose
- runny nose
- mucus dripping from the back of the nose down the throat (post-nasal drip)
- reduced sense of taste or smell
- feeling pressure across the face
- obstructive sleep apnoea (OSA) – your airways become temporarily blocked while you're asleep, which can disturb your sleep
- Sinusitis (facial pain, toothache and a high temperature)
Your doctor will discuss your symptoms and will examine the inside of your nose. You may be referred to an Ear, Nose and Throat (ENT) specialist for further tests to confirm the presence of nasal polyps, and to determine their number and size.
These tests may involve an endoscopy (where a small camera is inserted into your nostril) or a computed tomography (CT scan) may be required.