Does your nose seem blocked most of the time, even when you do not have a cold? Perhaps one side always feels harder to breathe through, the congestion comes and goes during the day, or it becomes noticeably worse when you lie down at night.

A blocked nose is a symptom rather than a condition on its own. It can happen when the tissues inside the nose become swollen, mucus builds up, the nasal airway is physically narrow, or several of these factors occur together.

Occasional nasal congestion is common and often settles on its own. However, if your nose regularly feels blocked or the problem continues for weeks or months, understanding the underlying cause becomes important.

When your nose feels blocked, it does not necessarily mean that it is simply full of mucus. Irritation or inflammation can cause the lining inside the nasal passages to swell, leaving less space for air to flow through comfortably.

In other cases, the nasal airway itself may be narrow because of the shape of the structures inside the nose. Some people experience blockage on both sides, while others find that one nostril is consistently more difficult to breathe through.

The blockage may also occur with symptoms such as a runny nose, sneezing, facial pressure, mouth breathing or a reduced sense of smell. Looking at these symptoms together can provide useful clues about what may be causing the problem

Allergic rhinitis happens when the body reacts to substances in the environment known as allergens. Common examples include house dust mites, mould and pet dander.

This reaction can cause the lining inside the nose to swell and produce more mucus, making it harder to breathe through the nose. Other symptoms may include frequent sneezing, an itchy nose, clear nasal discharge and itchy or watery eyes.

House dust mites are a particularly relevant allergen in Singapore and can trigger symptoms throughout the year in people who are sensitive to them. Paying attention to when and where symptoms become worse can sometimes help identify a possible allergy trigger.

Not everyone with a repeatedly blocked nose has an allergy. Non-allergic rhinitis can cause swelling inside the nose even when an allergic reaction is not responsible.

Possible triggers include cigarette smoke, strong smells, paint fumes and other irritating substances. Hormonal changes and certain medicines may also contribute to nasal congestion in some people.

Because the symptoms can look similar to allergic rhinitis, it may be difficult to tell the difference based on nasal blockage alone.

A viral cold commonly causes temporary congestion because the tissues inside the nose become swollen and produce more mucus. The blockage usually improves as the infection settles.

Sinusitis occurs when the sinuses, which are air-filled spaces around the nose and face, become inflamed. Nasal blockage may occur together with facial pain or pressure, thick nasal discharge and a reduced sense of smell.

Chronic sinusitis refers to sinus symptoms that continue for 12 weeks or longer. Someone who has been congested for several months should therefore not automatically assume that they are simply experiencing one cold after another.

However, a blocked nose on its own does not necessarily mean that you have sinusitis. The length of time the symptoms have been present and the other symptoms occurring alongside the congestion are also important.

Sometimes the main problem is not mucus or inflammation. The physical structure of the nasal passages can make it difficult for air to flow freely.

The septum is the wall separating the left and right sides of the nose. When it is significantly off-centre, known as a deviated septum, one side may be narrower and feel consistently more blocked.

Another possible structural problem involves the nasal valve, which is one of the narrowest parts of the nasal airway. If this area is too narrow or the sidewall moves inward during breathing, airflow may become restricted, particularly when taking a deep breath or exercising.

Turbinates are structures along the sides of the nasal passages that help warm and humidify the air we breathe. When the tissues covering them remain swollen, they can take up more room and restrict airflow.

Nasal polyps are soft, non-cancerous growths that can develop from the lining of the nose or sinuses. Larger polyps may contribute to ongoing nasal blockage and are sometimes associated with a gradual reduction in the sense of smell.

In children, enlarged adenoids can also restrict airflow at the back of the nose. This can contribute to persistent nasal blockage, mouth breathing or snoring.

The pattern of your nasal blockage can provide useful clues, although symptoms alone cannot confirm exactly what is causing the problem.

Congestion together with frequent sneezing, nasal itching and clear discharge may suggest allergic rhinitis. Itchy or watery eyes can be another clue that allergies may be involved.

If one nostril remains consistently more blocked, a structural issue such as a deviated septum may need to be considered. Persistent one-sided blockage should be assessed rather than repeatedly treated without knowing the cause.

A blocked nose with facial pressure, thick nasal discharge and reduced smell can occur with sinusitis. If these sinus-related symptoms continue for 12 weeks or longer, chronic sinusitis may be considered.

Meanwhile, long-term congestion accompanied by a gradual decline in the sense of smell can occur with nasal polyps. As several nasal conditions can produce similar symptoms, it is useful to consider the complete symptom pattern rather than focusing on one sign alone.

Some people breathe relatively comfortably during the day but become more congested when they go to bed. Lying down can make existing nasal swelling or narrowing feel more noticeable, particularly when the nose is already inflamed.

Allergies may also contribute if you are exposed to allergens in the bedroom. Someone who is sensitive to house dust mites, for example, may experience symptoms after spending long periods around bedding, mattresses or soft furnishings.

Persistent night-time blockage can encourage mouth breathing and may be associated with a dry mouth, snoring or disturbed sleep. If nasal congestion regularly affects your sleep, it is worth finding out what is restricting the airflow rather than relying only on temporary relief.

There is no single test that every person with a blocked nose requires. An ENT assessment usually begins with questions about how long the problem has been present, whether one or both sides are affected and what other symptoms occur.

The doctor may also ask whether the blockage is constant or comes and goes, whether it becomes worse at night and whether treatments such as antihistamines or nasal sprays have helped. The inside of the nose can then be examined for swelling, enlarged turbinates, polyps, discharge, a deviated septum or other narrowing.

In some cases, nasal endoscopy may be recommended. This involves passing a slim camera gently through the nose so the doctor can see areas that are difficult to examine during a basic nasal assessment.

It may help identify swelling, polyps, discharge or other problems further inside the nasal passages.

A CT scan may be considered when persistent sinus disease, nasal polyps or a more complex structural problem needs closer assessment. Imaging is not automatically required for everyone who has nasal congestion.

Whether further testing is needed depends on the symptoms and what is found during the examination.

The most appropriate treatment depends on why your nose is blocked. A treatment that helps inflammation caused by allergies, for example, cannot correct a significant structural narrowing.

Saline nasal sprays or rinses can help clear mucus and irritants from the nasal passages while keeping the lining moist. They may be useful as part of the treatment for several causes of nasal congestion.

If allergies or irritation are contributing to the problem, identifying possible triggers can also help. Reducing exposure to known allergens, cigarette smoke and strong irritants may lessen symptoms in some people.

Depending on the cause, treatment may include antihistamines for allergy symptoms or steroid nasal sprays to reduce inflammation inside the nose. Treatment should be matched to the underlying problem rather than assuming that every blocked nose needs the same medicine.

Decongestant nasal sprays can provide short-term relief, but many should not be used for more than about three days unless a healthcare professional advises otherwise. Using certain decongestant sprays for too long can cause rebound congestion, where the nose becomes blocked again as the spray wears off.

If you find yourself repeatedly relying on a decongestant spray because your nose becomes blocked again, speak with a doctor rather than increasing how often you use it.

When a physical narrowing is the main cause, medicines may reduce additional swelling but cannot change the underlying structure of the nose. A significantly deviated septum, for example, cannot be straightened with a nasal spray.

Surgery is not automatically required for persistent nasal blockage. It is usually considered only in selected patients when the main cause is structural or when significant symptoms continue despite appropriate medical treatment.

The first step is therefore to identify what is restricting the airflow before deciding which treatment is suitable.

Temporary congestion during a cold often improves as the infection settles. However, nasal blockage that persists, repeatedly returns or interferes with normal breathing deserves further assessment.

Consider seeing an ENT doctor if your blocked nose:

• Continues for a prolonged period or repeatedly returns.
• Regularly affects your sleep or everyday activities.
• Does not improve despite appropriate initial treatment.
• Remains consistently worse on one side.
• Occurs with an ongoing reduction in your sense of smell.
• Is associated with repeated nosebleeds or blood-stained discharge.
• Is gradually becoming worse.

Persistent one-sided blockage deserves particular attention, especially when accompanied by bleeding, facial numbness, double vision or a lump in the neck. These symptoms do not automatically mean that a serious condition is present, but they should be medically assessed rather than ignored.

A nose that constantly feels blocked is not always caused by a lingering cold. Allergic rhinitis, nasal irritation, sinusitis, swollen turbinates, nasal polyps and structural problems such as a deviated septum can all restrict airflow through the nose.

Pay attention to the pattern of your symptoms, including whether one or both nostrils are affected, whether the blockage becomes worse at night and whether you also experience sneezing, facial pressure, nasal discharge or changes in your sense of smell.

If nasal blockage continues, keeps returning or begins affecting your sleep and everyday activities, an ENT assessment can help identify the underlying cause. Once the reason for the obstruction is clear, treatment can focus on the actual problem rather than simply providing temporary relief.

1. Why is my nose always blocked even though I am not sick?
A blocked nose is not always caused by an infection. Allergic rhinitis, non-allergic rhinitis, enlarged turbinates, nasal polyps, a deviated septum and other forms of nasal narrowing can all cause congestion without a cold.
If the problem continues for several weeks or repeatedly returns, it may be useful to have the cause assessed rather than treating it each time as a temporary infection.

2. Why is one nostril always more blocked than the other?
Airflow naturally varies between the two nostrils during the day. However, if the same side remains consistently difficult to breathe through, a structural cause such as a deviated septum or another form of nasal narrowing may need to be considered.
Persistent one-sided blockage, particularly when it is worsening or accompanied by bleeding, should be assessed by a doctor.

3. Does a constantly blocked nose mean I have sinusitis?
No. Nasal blockage can occur with sinusitis, but congestion alone is not enough to diagnose it.
Sinusitis can also cause symptoms such as facial pain or pressure, thick nasal discharge and a reduced sense of smell. Chronic sinusitis involves symptoms continuing for at least 12 weeks.

4. Can allergies make my nose feel blocked every day?
Yes. If you are regularly exposed to an allergen that triggers allergic rhinitis, swelling and congestion inside the nose can repeatedly occur or persist for long periods.
Other symptoms such as sneezing, an itchy nose, clear nasal discharge and itchy or watery eyes may suggest that allergies are contributing.

5. Can a blocked nose affect my sleep?
Yes. Nasal obstruction can make breathing through the nose more difficult at night and may encourage mouth breathing, snoring or disturbed sleep.
If you regularly wake because you cannot breathe comfortably through your nose, or your nasal blockage is accompanied by significant snoring or pauses in breathing during sleep, a medical assessment is appropriate.