Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Chronic sinusitis or rhinitis means inflammation in the nose and sinuses that lasts weeks to months, with ongoing nasal discharge, sneezing, snorting, or noisy breathing. It usually has an underlying cause, such as dental disease, a foreign object, fungal infection, immune-related inflammation, or a tumor. Antibiotics often help only temporarily because bacteria are usually a secondary problem. Finding the cause, often with a CT scan and rhinoscopy, is the key to treatment.
Signs
- Nasal discharge lasting more than a couple of weeks (clear, cloudy, yellow-green, or bloody)
- Frequent sneezing or reverse sneezing
- Snoring, snorting, or noisy breathing
- Pawing at the face or rubbing the nose
- Nosebleeds
- Loss of pigment or sores on the nose (with some fungal infections)
- Facial swelling or pain
Common causes
- Dental disease: infected upper tooth roots can drain into the nose.
- Foreign bodies, such as grass awns.
- Fungal infection: nasal aspergillosis, most common in long-nosed breeds, often causes discharge, nosebleeds, and pain.
- Lymphoplasmacytic (inflammatory) rhinitis: an immune-related inflammation with no single cause.
- Nasal tumors, more common in older dogs, often with one-sided discharge or nosebleeds.
- Nasal mites (less common).
- Allergies in some dogs.
When to see a vet
See your vet for nasal discharge lasting more than a few days, one-sided discharge, nosebleeds, facial swelling, or noisy breathing. Go urgently for difficulty breathing, blue or gray gums, or a heavy nosebleed.
Diagnosis
- Exam of the mouth, teeth, and face
- Bloodwork and clotting tests (especially with nosebleeds)
- CT scan of the nose and sinuses, the most useful imaging test
- Rhinoscopy (a camera in the nose) to look for foreign bodies, fungus, or masses, and take samples
- Biopsy and culture
- Fungal blood tests in some cases
Treatment
- Dental disease: extraction or treatment of the infected tooth.
- Foreign bodies: removal, often during rhinoscopy.
- Aspergillosis: removing fungal plaques and infusing antifungal medication into the nose and sinuses under anesthesia, sometimes with oral antifungals. Treatment may need repeating.
- Inflammatory rhinitis: managed rather than cured, with anti-inflammatory medication, humidification, and sometimes other drugs.
- Tumors: radiation therapy is the most common treatment.
- Antibiotics for secondary bacterial infection, usually as a short-term part of the plan.
Home care
- Humidity: a cool-mist humidifier or steam from a shower (never leave your dog alone in a hot room).
- Keep the nose clean with a soft, damp cloth.
- Plain saline drops only if your vet recommends them.
- Avoid smoke, dust, and strong scents in the home.
- Use a harness instead of a collar if your dog has noisy breathing.
What to avoid
- Human decongestants (pseudoephedrine, phenylephrine): can be very dangerous for dogs.
- Medicated human nasal sprays unless prescribed.
- Essential oils and vapor rubs.
- Repeated antibiotic courses without a diagnosis, which delay finding the real cause and encourage resistant bacteria.
For short-term stuffiness, see our guide to nasal congestion in dogs.
Frequently asked questions
Why does my dog’s nasal discharge keep coming back after antibiotics?
Because bacteria are usually not the root cause. An underlying problem like a tooth infection, fungus, or foreign object needs to be found.
Is chronic rhinitis in dogs contagious?
Usually not. Most causes, such as dental disease, inflammation, or fungal infection, don’t spread between dogs.
Can chronic rhinitis be cured?
It depends on the cause. Foreign bodies and dental causes can often be cured. Inflammatory rhinitis is usually managed long term.
Sources
- Merck Veterinary Manual: Rhinitis and sinusitis in dogs
- Merck Veterinary Manual: Aspergillosis in dogs
- Windsor RC, Johnson LR. Canine chronic inflammatory rhinitis. Clin Tech Small Anim Pract. 2006
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.