Most people with a deviated septum can spot the signs at home by checking for uneven airflow between their nostrils and looking at their nose shape. The tricky part is that up to 80% of people have some degree of septal deviation, and many never notice it. What matters is whether yours is causing problems like chronic congestion, trouble breathing, or repeated sinus infections.
The Simple Self-Test
The easiest way to check at home is the nostril breathing test. Use your finger to hold one nostril closed, breathe in through the open side, and pay attention to how easily air flows. Then switch sides and repeat. If one side feels noticeably more blocked than the other, and that pattern stays consistent day after day, a deviated septum is a likely cause.
You can also check visually. Look straight into a mirror and see if your nose appears off-center. If it looks fine from the front, try taking a photo of the underside of your nose. Uneven or differently sized nostrils are a visual clue. A severe deviation can make the entire nose look crooked, but milder cases often look normal from the outside while still restricting airflow inside.
Symptoms That Point to a Deviated Septum
One-sided nasal congestion is the hallmark symptom. Allergies and colds cause stuffiness on both sides that comes and goes, but a deviated septum typically blocks the same side consistently. You might notice it most at night when lying down, because gravity shifts blood flow and swells the nasal tissue on the narrowed side even further.
Other common signs include:
- Nosebleeds. The narrower side dries out faster because air moves through a tighter space, making the lining crack and bleed.
- Mouth breathing and snoring. When one nasal passage is significantly blocked, you compensate by breathing through your mouth, especially during sleep.
- Facial pressure or headaches. A deviated septum can press against the inner wall of the nose, creating a dull ache around the cheeks or forehead.
- Repeated sinus infections. A narrowed passage traps mucus, creating a breeding ground for bacteria. If you get sinus infections several times a year, the septum could be part of the problem.
These symptoms overlap with other conditions, so the pattern matters more than any single symptom. A deviated septum tends to produce a predictable, one-sided set of issues that doesn’t fully respond to allergy medication or decongestants.
How It Differs From Allergies and Polyps
Allergic rhinitis causes congestion, sneezing, and a runny nose, but it affects both sides and responds to antihistamines. If your stuffiness clears up with allergy medication, the septum probably isn’t your main issue.
Nasal polyps, soft noncancerous growths inside the nose, can mimic a deviated septum because they also block airflow. But polyps tend to cause loss of smell and taste, heavy postnasal drip, and congestion on both sides. They usually appear in both nostrils. A growth on only one side warrants a closer look by a doctor, since that pattern is less typical for polyps. The key difference: a deviated septum is a structural problem with the wall itself, while polyps are tissue growths hanging in the airway.
What a Doctor Actually Does to Confirm It
An ear, nose, and throat specialist can usually diagnose a deviated septum with a simple in-office exam. They’ll look inside your nostrils with a bright light and a small handheld instrument that gently opens the nasal passage. In some cases, they’ll use a nasal endoscope, a thin flexible tube with a camera and light, threaded into your nose to get a detailed view of the septum, sinuses, and surrounding structures. The procedure takes a few minutes and feels like mild pressure.
During the exam, the doctor checks for the deviation itself and also looks for other causes of obstruction, like polyps, swollen turbinates (the ridges inside your nose that warm and humidify air), or tumors. They may apply a numbing spray and then a decongestant to see how much of your congestion is from swelling versus the structural deviation. If your breathing improves significantly with the decongestant, swelling is playing a bigger role. If it doesn’t, the septum is more likely the culprit.
How Severity Is Graded
Not all deviations are equal. Doctors grade them based on how far the septum shifts from the center toward the outer wall of the nose. A mild deviation (roughly the first third of the distance toward the side wall) rarely causes noticeable symptoms. A moderate deviation reaches about halfway across. A severe deviation pushes most of the way to the outer wall, sometimes pressing directly against the structures inside the nose.
The shape of the curve matters too. A C-shaped deviation bends to one side, blocking that nostril. An S-shaped deviation curves in both directions, potentially narrowing both nasal passages at different points. Some people have a bony spur, a sharp ridge of bone or cartilage jutting off the septum, that pokes into the airway at a single spot. Each pattern creates a slightly different set of symptoms, and the shape influences what kind of correction would be needed.
The Connection to Sleep Problems
A significant deviation doesn’t just make daytime breathing harder. A large study tracking patients over nine years found that people with a major septal deviation were more than four times as likely to develop obstructive sleep apnea compared to people without one. The risk climbed higher in people with a higher body weight. Surgical correction of the septum reduced that risk by about 29%, and for people already using a CPAP machine for sleep apnea, fixing the deviation made it easier to tolerate the device.
If you snore heavily, wake up feeling unrested, or have been told you stop breathing during sleep, a deviated septum could be a contributing factor worth investigating.
When the Deviation Needs Treatment
A deviated septum only needs treatment when it causes persistent symptoms that affect your quality of life. Many people live with a mild or moderate deviation and never need intervention. Nasal steroid sprays and saline rinses can reduce swelling enough to open the airway in borderline cases.
Surgery, called septoplasty, becomes the main option when symptoms don’t respond to these measures. No medication can physically straighten a crooked septum, so surgery is the only way to correct the structure itself. According to guidelines from the American Academy of Otolaryngology, septoplasty is considered appropriate when a documented deviation is present alongside persistent symptoms, and the exam confirms the deviation is causing or contributing to the obstruction rather than something else like polyps or swollen tissue.
Septoplasty is typically an outpatient procedure, meaning you go home the same day. Recovery involves about a week of congestion and soreness, with most people returning to normal activities within two to three weeks. The goal is to reposition the septum closer to the center, widening the blocked passage so air flows more evenly through both sides.