Sinus & Nose 22 August 2026 · 5 min read · By Dr. James Cole
Up to 80 percent of people have a septum that isn't perfectly straight — and most never notice. But when the bend is significant, one-sided blockage, mouth breathing, and repeat sinus infections become a way of life. Here's how to tell the difference.
The telltale pattern
A deviated septum typically blocks one side more than the other, worsens with colds and allergies, and pairs with noisy nighttime breathing, dry mouth in the morning, and nosebleeds on the narrow side. If decongestants give only brief relief and the blockage always returns to the same side, the structure — not just swelling — is likely involved.
Diagnosis takes minutes
A nasal endoscopy — a thin camera passed gently into the nostril — shows the septum, turbinates, and drainage pathways directly. Combined with your symptom history, it usually answers the question in a single visit. CT imaging is reserved for surgical planning or complex sinus disease.
Treatment is stepwise
Saline rinses, steroid sprays, and allergy control manage mild cases well. When obstruction persists despite proper medical treatment — or drives recurrent sinusitis — septoplasty straightens the septum through a short day-case procedure, often combined with turbinate reduction. Most patients breathe freely within two to three weeks.
Always blocked on one side? Book a nose and sinus assessment and get a clear answer in one visit.