How a normal nose looks like

There are various common causes for a blocked nose.  They could be due to infection, allergies, turbinates enlargement, structural causes, nasal polyps or adenoid enlargement for children. Very often, a combination of factors contributed to the nasal congestion.

How does an infection cause blocked nose?

A cold, flu, allergies or infection can all inflame the blood vessels causing swelling of the nasal tissues and stimulates the nasal membranes to product excessive amounts of mucus, clogging the nose.

How does allergies cause blocked nose?

Rhinitis is characterised by sneezing, tearing in the eyes and blocked nose. Most of us would have experienced it before. While spring cleaning our house, changing the bed sheets, or sweeping the floor, we get caught in a frenzied episode of sneezing, tearing in the eyes and blocked nose.  Rhinitis is an exaggerated inflammatory response in the nose due to a foreign substance such as dust mites, moulds etc.  The release of histamines results in nasal congestion.

There are often confusions between rhinitis and sinusitis.  

Many patients mistaken these symptoms as ‘sinus’.  Sinus refers to the air filled spaces in our facial bones.  Mucus will flow out of the sinus through narrow drainage pathways and into the nose.  When sinus becomes inflamed or infected, they clog up the openings of the sinus.  This causes fluid to build up inside the sinuses due to pressure, resulting in sinusitis.

How do we treat allergic rhinitis/nasal allergies?

The doctor may prescribe a nasal spray. Sometimes, it may be prescribed together with antihistamines. The medications may need to be sustained over a period of time to be effective.

If nasal obstruction or congestion is severe due to enlarged turbinates or crooked nose bone, a simple procedure can be done to reduce the size of the turbinates or to correct the crooked nasal septum.

In patients with severe symptoms, immunotherapy may be recommended.

How does enlarged turbinates cause blocked nose?

There are 3 turbinates on each side of our nose. They are the inferior, middle and superior turbinates. Enlarged turbinate (hypertrophy of turbinate) will cause nasal congestion. 

How enlarged lower turbinates look like
Left middle turbinate is enlarged and filled with air (pneumatised)

Rhinitis (due to allergies) could stimulate allergic reactions causing swollen turbinates which will obstruct the nasal passageway.  This could stimulate excessive production of mucus which would drip back to the throat causing cough, throat discomfort, post nasal drip.  This could be resolved by medications using a combination of nasal sprays, oral anithistamines, oral antibiotics.  

An enlarged turbinate could cause nasal obstruction and affect breathing. A simple surgical procedure to trim the size of the turbinates, decrease airway resistance would greatly reduce the blocked nose.

Turbinate reduction

What are the structural causes of blocked nose? (Deviated Nasal Septum)

Deviated nasal septum
Nasal septum is pressing onto middle turbinate

The nasal septum is the cartilage and bone that separates the right and left airways in the nasal cavities.  It should ideally run down the centre, as it enables the air we breathe in to go smoothly into our lungs.

It is natural for some forms of nasal deviation to happen. However, severe imbalances will cause one sided (unilateral) nasal problems but this could be easily corrected via a simple procedure to correct the crooked septum. This procedure is known as Septoplasty

Severe deviation of the nasal septum could lead to difficulty in breathing, sinus infection, snoring and sleep apnea.

How does nasal polyps cause blocked nose?

Polyps starts to form in ethnoid sinus
Polyps reaches the floor of nose, causing complete nasal obstruction

Nasal polyps are painless, teardrop-shaped, noncancerous growths on the lining of your nasal passages or sinuses. They usually appear as semi transparent and they come in a variety of sizes and are more common among middle-aged adults.

Small nasal polyps may not cause any problem and could go unnoticed. Larger nasal polyps can block your nasal passages or sinuses causing nasal obstruction and sometimes, a loss of sense of smell (anosmia).

Nasal polyps can be safely removed via a functional endoscopic sinus surgery done under image guidance. It is a safe procedure done under skilled hands. 

How does enlarged adenoids cause blocked nose? 

Adenoids located in the postnasal space

Adenoids are tiny pieces of tissue at the back of your throat. You will be able to see your tonsils at the back of your throat but you cannot see your adenoids.

By age 6, most adenoids would shrink in size. The adenoids become a liability when:

  • They become infected (Adenoiditis)
  • They grow too large in size (Adenoid hypertrophy)
Direct visualisation with fiberoptic endoscope
How does enlarged adenoids cause blocked nose?

Video Explanations

1.  Understand why your nose and sinus are blocked

Dr Kevin Soh reveals the different causes for block nose. He illustrates with interesting graphics and videos. Understand deviated nasal septum, nasal polyps, enlarged adenoids.

2. How to get rid of blocked nose and sinusitis

Dr Soh gave a talk on block nose, sinusitis diagnosis and treatment to staff of ST Engineering. Click here to see the contents of the talk.