What is a deviated septum?
The nasal septum is the thin wall of cartilage and bone that divides the inside of the nose into two nostrils. Ideally it sits roughly in the centre, giving two nasal passages of similar size. A deviated septum is when this wall is off-centre, bent or crooked, so that one nasal passage is narrower than the other. This is extremely common — a great many people have some degree of septal deviation, often without ever knowing or being troubled by it.
A deviated septum can be present from birth or can result from an injury to the nose, such as a knock or break, which pushes the septum out of alignment. Whether it causes symptoms depends largely on how significant the deviation is and where it sits. A minor deviation usually causes no problems at all, while a more marked one can noticeably restrict airflow through one or both nostrils and contribute to other nasal symptoms.
Symptoms of a deviated septum
Many deviated septa cause no symptoms, but when they do, the effects centre on nasal airflow and breathing. Common symptoms include:
- •A blocked or congested nose, often worse on one side
- •Difficulty breathing through the nose, particularly one nostril
- •Nasal congestion that does not fully clear, or alternates sides
- •Snoring or noisy breathing during sleep
- •A tendency to recurrent sinus infections
- •Nosebleeds, if the deviation dries out one side of the nose
- •Sometimes a preference for sleeping on a particular side to breathe better
How a deviated septum affects breathing and sleep
When a deviated septum narrows one or both nasal passages significantly, it restricts the flow of air through the nose. This can make nasal breathing feel like hard work, particularly during exercise or when lying down, and often leads people to breathe through the mouth, especially at night. Because the effect is often one-sided, a characteristic experience is finding that one nostril is reliably more blocked than the other.
Restricted nasal airflow from a deviated septum can also contribute to snoring, as air is forced through a narrower space and mouth breathing becomes more likely during sleep. A deviated septum can worsen the impact of colds and allergies, since there is less room to spare when the lining swells, and it can predispose to sinus problems by impairing drainage. Recognising a deviated septum as the underlying factor helps explain a range of persistent nasal symptoms.
Treatment for a deviated septum
Many people with a deviated septum need no treatment at all, particularly if symptoms are mild. Where symptoms are troublesome but related to swelling of the nasal lining — for example from allergies or congestion — treatments aimed at that swelling can help, such as steroid nasal sprays, antihistamines for allergies, or saline rinses. These do not straighten the septum but can improve airflow by reducing the swelling that adds to the blockage, and are often tried first.
When a deviated septum causes significant, persistent symptoms that do not respond to these measures, surgery to straighten the septum — an operation called septoplasty — can be considered. This straightens and repositions the septum to open up the nasal passages and improve breathing. It is a common and generally effective procedure. A specialist can assess whether the septum is the main cause of the symptoms and whether surgery is likely to help, as not all nasal blockage is due to the septum.
Deviated septum, sinuses and other causes
A blocked nose has many possible causes, and a deviated septum is only one of them, so it is worth considering the whole picture. Allergies, chronic sinusitis, nasal polyps, and simple congestion from colds can all cause similar symptoms, and often several factors combine. This is why a persistently blocked nose is worth having assessed rather than assumed to be one thing — treatment is most effective when aimed at the actual cause or causes.
In particular, if nasal blockage comes with facial pressure, reduced sense of smell, or thick discharge, sinus problems or nasal polyps may be contributing alongside or instead of a deviated septum. A doctor or ENT specialist can examine the nose, sometimes with a small scope, to see the septum and the rest of the nasal passages, and work out what is driving the symptoms. This ensures that any treatment, whether medical or surgical, is directed at the right target.
When to see a doctor
You should see a doctor if a blocked nose or difficulty breathing through the nose is persistent, troublesome, or affecting your sleep or quality of life, especially if it does not clear with simple measures. While a deviated septum is often harmless, assessment can confirm whether it is the cause and whether treatment would help, and can identify other contributing factors like allergies or sinus problems that have their own treatments.
It is also worth seeking advice if nasal blockage follows an injury to the nose, if you have frequent nosebleeds or recurrent sinus infections, or if snoring linked to nasal blockage is affecting you or a partner. For symptoms that do not respond to sprays and allergy treatment, a referral to an ENT specialist allows a proper assessment of the septum and consideration of whether septoplasty would help. Most nasal blockage, though, can be improved once the cause is clear.