News

How to Tell If You Have a Deviated Septum: Signs and Self-Check Guide

How to Tell If You Have a Deviated Septum: Signs and Self-Check Guide

Learn how to recognise the signs of a deviated septum, try a simple self-check and understand when to seek medical advice for ongoing nasal blockage.


Do you often breathe better through one nostril than the other? Do you regularly wake up with a blocked nose or find yourself relying on mouth breathing, especially at night? While occasional nasal congestion is common, persistent blockage on one side of the nose could be a sign of a deviated septum. This condition affects many people, and in some cases, it can contribute to snoring, poor sleep quality and make CPAP therapy more challenging.

What Is a Deviated Septum?

The nasal septum is the wall made of bone and cartilage that separates your left and right nasal passages. Ideally, it sits close to the centre of the nose, allowing air to flow evenly through both nostrils.

A deviated septum occurs when this wall is significantly off-centre or crooked, making one nasal passage narrower than the other. Some people are born with a deviated septum, while others develop one after an injury to the nose. Many mild deviations cause no symptoms, but more severe cases can affect breathing and sleep.

Normal Septum vs Deviated Septum — Cross-Section View 💨 💨 Normal Septum Equal airflow both sides 🚫 💨 Deviated Septum One side restricted Left Right Left Right
A simplified cross-section showing a centred septum (left) allowing equal airflow through both nasal passages, and a deviated septum (right) where the displaced wall narrows one passage and restricts airflow on that side.

Common Signs of a Deviated Septum

Symptoms vary depending on how much the septum is displaced. Symptoms may become more noticeable during a cold or allergy flare-up, when the nasal passages are already swollen.

👃
Recognised Symptoms
How a deviated septum commonly presents
Nasal and Breathing Symptoms
Blocked nose usually worse one side Difficulty breathing through one nostril Frequent mouth breathing Recurrent nosebleeds Frequent sinus infections Reduced sense of smell
The most characteristic sign is persistent blockage that is noticeably worse on one side of the nose. Unlike congestion from a cold or allergy, which tends to affect both sides and fluctuates, blockage from a structural deviation tends to be one-sided and relatively constant. Recurrent nosebleeds may occur if the deviated septum dries out more easily on one side due to altered airflow patterns.
Sleep and Night-Time Symptoms
Snoring Noisy breathing during sleep Waking with a dry mouth May worsen with colds or allergies
Nasal obstruction during sleep encourages mouth breathing, which in turn promotes snoring and dry mouth on waking. A deviated septum does not directly cause obstructive sleep apnoea, but it may make breathing less comfortable and can contribute to snoring or worsen symptoms in people who already have sleep-disordered breathing.
Other Symptoms
Facial pressure or discomfort May indicate secondary sinusitis
Facial pressure or discomfort, particularly around the cheeks and forehead, can result from impaired sinus drainage secondary to the structural obstruction. This is not always caused by the deviation itself in many cases it reflects recurrent sinus infections that the narrowed passage makes more likely.

Why a Deviated Septum Can Affect Sleep

Breathing comfortably through your nose plays an important role in healthy sleep. If one side of your nose is consistently blocked, you may notice several sleep-related consequences.

  • Breathing through your mouth while sleeping
  • Snoring more frequently
  • Waking feeling less refreshed
  • Experiencing interrupted sleep
  • Noticing increased daytime tiredness
Important distinction: A deviated septum does not directly cause obstructive sleep apnoea, but it may make breathing less comfortable and can contribute to snoring or worsen symptoms in people who already have sleep-disordered breathing.

A Simple Self-Check at Home

A deviated septum self-check cannot confirm a diagnosis, but it may help you recognise possible signs worth discussing with a healthcare professional.

1
Compare Airflow Through Each Nostril
Close one nostril gently and breathe through the other. Repeat on the opposite side. If one side consistently feels much more restricted, it may indicate a structural blockage rather than temporary congestion.
2
Look in a Mirror
Using a torch and a mirror, gently lift the tip of your nose. You may notice that the septum appears off-centre. Keep in mind that the inside of the nose is difficult to assess without specialist equipment, so this is only a rough observation.
3
Pay Attention While Exercising
Do you struggle to breathe through your nose during gentle activity? Persistent one-sided blockage during exercise may be worth discussing with a healthcare professional.
4
Notice How You Sleep
Ask yourself: Do you regularly wake with a blocked nose? Do you switch sides to breathe more easily? Does one nostril seem permanently blocked? Patterns like these can provide useful information for your GP or ENT specialist.
💡 Remember: A deviated septum self-check may help you recognise possible signs, but it should not replace a professional assessment. Although only a healthcare professional can diagnose a deviated septum, recognising the common signs at home may help you decide whether it’s worth seeking medical advice.

Could It Be Something Else?

Not every blocked nose is caused by a deviated septum. Because these conditions can produce similar symptoms, a medical assessment is often needed to identify the true cause.

  • Seasonal allergies
  • Hay fever
  • Viral infections
  • Nasal polyps
  • Enlarged turbinates
  • Chronic sinusitis
  • Dry indoor air

How Is a Deviated Septum Diagnosed?

If your symptoms are persistent or affecting your sleep, your GP may refer you to an ear, nose and throat (ENT) specialist. Imaging tests are not usually required unless another condition is suspected.

Typical Diagnosis Pathway for Deviated Septum 🩺 GP Appointment Symptoms & medical history First contact 👁️ ENT Referral Nasal speculum examination If symptoms persist 🔦 Nasal Endoscopy Small camera to view passages If needed 💨 Airflow Assessment Each nostril assessed for restriction Confirms severity 📋 Treatment Plan Based on severity and symptoms Tailored to you
The typical diagnostic pathway for a deviated septum in the UK from GP appointment through to ENT specialist assessment and treatment planning. Imaging is not usually required unless another condition is suspected alongside the deviation.

Treatment Options

Treatment depends on how severe your symptoms are. Options range from simple lifestyle measures through to surgery, and the most appropriate approach is guided by how significantly the deviation affects daily life and sleep.

🧴
Lifestyle Measures

If symptoms are mild, your healthcare professional may recommend saline nasal sprays, saline rinses, avoiding known allergy triggers, or using a humidifier during dry weather. These approaches won’t straighten the septum but may help reduce swelling and improve airflow.

💊
Medication

If inflammation is contributing to nasal blockage, treatments may include steroid nasal sprays, antihistamines for allergies, or decongestants for short-term use only. Medication can relieve swelling but cannot correct the position of the septum itself.

🔬
Septoplasty

For people with significant symptoms that don’t improve with conservative treatment, surgery called septoplasty may be recommended. Septoplasty straightens the nasal septum to improve airflow and breathing. Recovery varies, but many people notice improved nasal breathing once healing is complete. Your ENT specialist will explain whether surgery is appropriate for your individual circumstances.

⏳
Watchful Waiting

Many people have a mild deviation that causes few or no symptoms and requires no treatment at all. If symptoms are present but manageable with conservative measures, watchful waiting alongside symptom management is a valid and commonly chosen approach.

Can a Deviated Septum Affect CPAP Therapy?

For people using CPAP to treat obstructive sleep apnoea, nasal blockage can sometimes make therapy less comfortable.


How a Deviated Septum Can Affect CPAP Use
These challenges are usually manageable without surgery
  • Difficulty using a nasal mask
  • Mouth breathing during sleep
  • Air leaks
  • Reduced comfort
  • Feeling that airflow is restricted

In many cases, these challenges can be managed by trying a different mask style, adjusting humidification settings, using heated tubing, or treating nasal inflammation where appropriate. If nasal obstruction continues to interfere with therapy, speak with your sleep specialist or ENT clinician.

When Should You See a Doctor?

Arrange a medical assessment if you experience any of the following. Prompt assessment is especially important if symptoms develop after a facial injury.

  • Ongoing nasal blockage on one side
  • Frequent nosebleeds
  • Recurrent sinus infections
  • Persistent snoring
  • Difficulty breathing through your nose
  • Symptoms affecting sleep or CPAP therapy
  • Facial pain or pressure that doesn’t improve

Frequently Asked Questions

Can I diagnose a deviated septum myself?
No. A home assessment may help you recognise possible signs, but only a healthcare professional can confirm the diagnosis.
Does everyone with a deviated septum need surgery?
No. Many people have a mild deviation that causes few or no symptoms. Surgery is generally considered only when symptoms significantly affect breathing or quality of life.
Can a deviated septum cause sleep apnoea?
A deviated septum alone is not considered a direct cause of obstructive sleep apnoea. However, it can increase nasal resistance and make breathing during sleep less comfortable, particularly in people with existing sleep-disordered breathing.
Will CPAP still work if I have a deviated septum?
Yes. Many people with a deviated septum use CPAP successfully. Your sleep team may recommend a different mask style or adjustments to improve comfort if nasal obstruction is an issue.
Can allergies make a deviated septum feel worse?
Yes. Swelling caused by allergies or a cold can further narrow the nasal passages, making symptoms more noticeable.

Final Thoughts

A blocked nose isn’t always caused by a cold or allergies. For some people, it may be the result of a deviated septum, especially if one side of the nose always feels more restricted than the other.

A simple deviated septum self-check can help you recognise potential signs, but it shouldn’t replace a professional assessment. If ongoing nasal obstruction is affecting your sleep, daily activities or CPAP therapy, speaking with your GP or an ENT specialist is the best next step. With the right diagnosis and treatment, many people experience improved breathing, better sleep quality and greater comfort both during the day and at night.

Previous
Cheyne-Stokes Breathing: Causes, Symptoms and Treatment Options