Nose and Sinus Inflammation in Dogs (Rhinitis and Sinusitis)

  • Occurrence: common
  • Location of disease: Head/Neck
Author: Dr. med. vet. Gisa Löwe | Last modified: 15.10.2026
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When to visit the vet?

Non-urgent see a veterinarian within 2–3 days

?

If the condition worsens / symptoms persist, consult a veterinarian.

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Definition

Rhinitis and sinusitis in dogs are inflammatory conditions of the nasal mucosa and sinuses that can be caused by a variety of factors and lead to respiratory distress.

The most important facts at a glance

Rhinitis and sinusitis in dogs are inflammatory conditions of the nasal mucosa and sinuses. These diseases can be triggered by infections with viruses, bacteria, or, less commonly, fungi like Aspergillus. Allergies to pollen, dust mites, or molds, as well as environmental factors like smoke and dust, can also be causes. Anatomical anomalies or tumors in the nasal cavity are also possible triggers.

Typical symptoms include sneezing, nasal discharge, congested nasal passages, and respiratory distress. Diagnosis is made through a veterinary examination, possibly supported by X-rays or CT scans, and rhinoscopy for sample collection. Laboratory tests can help determine the exact cause.

Treatment depends on the cause. Bacterial infections require antibiotics, while viral infections are usually treated supportively. Allergic rhinitis can be treated with antihistamines or corticosteroids. For fungal infections, specific antifungals are required, and surgical interventions may be necessary to remove tumors or polyps.

The prognosis varies depending on the cause and severity, with acute infections often being well treatable. Chronic or allergic forms may require long-term treatment. Preventive measures include minimizing exposure to irritants and allergens, regular veterinary check-ups, and a healthy lifestyle. Vaccinations against certain viruses can also be helpful.

Causes

A dog’s nasal cavity is a complex system that plays an important role in filtering, humidifying, and warming inhaled air. It is lined with a mucous membrane that is traversed by a network of blood vessels and nerves. This mucous membrane is susceptible to inflammatory conditions, which are referred to as rhinitis. If the inflammatory conditions spread to the sinuses, it is called sinusitis.

Rhinitis and sinusitis can be triggered by a variety of factors. Infections by viruses, bacteria, or fungi are common causes. Viral pathogens include canine parainfluenza virus and canine adenovirus. Bacterial infections can occur primarily or secondarily to viral infections. Fungal infections, such as those caused by Aspergillus, are rarer but particularly significant in certain dog breeds.

Allergy is another common cause of rhinitis in dogs. Inhalant allergens such as pollen, house dust mites, or molds can trigger allergic rhinitis. Environmental factors such as smoke, dust, or chemical irritants can also irritate and inflame the nasal mucosa.

Additionally, anatomical anomalies, such as narrowing of the nasal passages or polyps, as well as traumatic injuries to the nose, can lead to rhinitis and sinusitis. Tumors in the nasal cavity or sinuses can also play a role.

Symptoms

Rare symptoms:

Dogs with rhinitis and sinusitis often show symptoms such as nasal discharge, which can be clear, mucous, or purulent. The discharge may come from one or both nostrils. Chronic cases can lead to crusting around the nostrils.

Sneezing is another common symptom and can be accompanied by nosebleeds in severe cases. Some dogs also show swelling in the area of the nasal cavities or around the eyes, indicating a spread of the inflammatory conditions to the sinuses.

Affected dogs may show respiratory sounds such as Snoring or rattling, especially if the nasal passages are narrowed. In severe cases, respiratory distress may also occur.

In chronic or severe infections, systemic symptoms such as Fever, loss of appetite, or lethargy may occur, indicating a general impairment of the dog’s well-being.

Therapy

The treatment of rhinitis and sinusitis in dogs depends on the underlying cause. For bacterial infections, antibiotics are usually used. The choice of antibiotic is based on the results of culture and sensitivity tests.

For viral infections, treatment is usually supportive, as antibiotics are ineffective against viruses. Support may include providing a warm, humid environment and administering mucolytic medications to facilitate nasal discharge.

For allergic rhinitis, antihistamines or corticosteroids may be used to control the inflammatory conditions. In some cases, hyposensitization therapy may be considered.

For fungal infections, specific antifungals are required, which often need to be administered over a longer period. Surgical interventions may be necessary to remove foreign bodies, polyps, or tumors.

Prognosis and follow-up care

The prognosis for dogs with rhinitis and sinusitis depends on the cause and severity of the condition. Acute viral or bacterial infections usually respond well to therapy, and symptoms often resolve within a few weeks.

Chronic or allergic rhinitis can be more difficult to control and may require a long-term management strategy. For fungal infections or tumors, the prognosis may be more guarded depending on treatment efficacy and disease progression.

In general, the prognosis is better if the condition is diagnosed and treated early. Regular veterinary follow-up is important to prevent relapses and maintain the dog’s quality of life.

Prevention

To prevent rhinitis and sinusitis in dogs, it is important to minimize exposure to potential triggers. This may include avoiding irritants such as cigarette smoke, strong chemicals, or dust.

For dogs prone to allergies, regular cleaning of the living environment can help reduce exposure to allergens. The use of air purifiers and frequent washing of dog beds can also be helpful.

Regular veterinary check-ups can help detect early signs of nasal problems and enable timely intervention. For dogs with known allergies, prophylactic treatment or hyposensitization may be considered.

A balanced diet and a healthy immune system can help reduce the risk of infection. Vaccinations against certain viral pathogens can also be part of a preventive health plan.

Outlook on current research

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Rhinitis and sinusitis are increasingly understood today as part of a common disease complex, often summarized as rhinosinusitis. The most important research advance is that these diseases are no longer classified solely by symptoms such as nasal congestion, secretion, or pressure, but by biological inflammatory patterns. Particularly important are the mucosal barrier, the microbiome, local biofilms, and different immune responses, such as type 2 inflammation. (pubmed.ncbi.nlm.nih.gov, pubmed.ncbi.nlm.nih.gov)

A central field of research is more precise diagnostics. The goal is to identify early whether an allergic, infectious, chronic inflammatory, or structurally related form is present. For this purpose, biomarkers, improved endoscopy, imaging, and standardized progression parameters are being further developed. In the long term, this should help avoid unnecessary antibiotic use and treat patients more targeted. (pubmed.ncbi.nlm.nih.gov, pubmed.ncbi.nlm.nih.gov)

Therapeutically, the outlook is particularly dynamic. For chronic rhinosinusitis with nasal polyps, biologics are gaining importance, i.e., targeted medications that attack specific inflammatory pathways. In parallel, research is being conducted into the role that microbiome-modulating approaches, better local drug delivery systems, and individualized surgical strategies can play in the future. (pubmed.ncbi.nlm.nih.gov, pubmed.ncbi.nlm.nih.gov)

Overall, research is clearly moving from the non-specific treatment of “clogged sinuses” to a more precise, inflammation-biologically based rhinosinusitis medicine.

Frequently Asked Questions (FAQs)

1. What are rhinitis and sinusitis?
Rhinitis is an inflammatory condition of the nasal mucosa, while sinusitis affects the paranasal sinuses. Since both mucous membranes are anatomically connected, the conditions often occur together (rhinosinusitis). They can be acute or chronic.
2. What are the causes?
Common causes include viral (parainfluenza, canine distemper), bacterial, and fungal infections (especially Aspergillus), foreign bodies like grass awns, dental root diseases with oronasal fistula, tumors of the nasal cavity, allergies, and traumas. Idiopathic, chronic lymphoplasmacytic rhinitis also occurs.
3. What symptoms do affected dogs show?
Typical symptoms include nasal discharge (clear, mucous, purulent, or bloody), sneezing, snoring sounds, nosebleeds, and respiratory distress. In unilateral rhinitis, foreign bodies, fungal diseases, or tumor diseases are particularly likely. Chronic courses are often accompanied by weight loss and a reduction in general condition.
4. How is the diagnosis made?
A thorough examination includes nasal X-rays or, preferably, CT, rhinoscopy with flushes and biopsies, as well as cytological, histological, and microbiological examination of the material. Dental control and, if necessary, endoscopy of the nasopharynx are important additions.
5. How is rhinitis treated?
Therapy depends on the cause. Bacterial infections are treated with antibiotics, fungal infections with topical clotrimazole infusion under anesthesia. Foreign bodies are removed rhinoscopically with fine forceps. Chronic idiopathic forms are treated with corticosteroids, inhalation therapy, and mucolytics.
6. What is nasal aspergillosis?
Nasal aspergillosis is a fungal infection with Aspergillus fumigatus, which primarily occurs in middle-aged, mesocephalic dogs. Characteristic symptoms include unilateral, bloody nasal discharge, pain on the nasal bridge, and depigmentation of the nose. Therapy involves a one-hour topical clotrimazole infusion.
7. What signs indicate a nasal tumor?
Nasal tumors primarily occur in older, dolichocephalic dogs. Typical symptoms include unilateral nasal discharge, progressive facial deformation, nosebleeds, and epiphora. Adenocarcinomas and carcinomas of other mucosal cells are the most common tumors. Diagnosis and therapy require CT and a targeted biopsy.
8. How are foreign bodies removed?
Grass seeds, awns, or hay particles are removed rhinoscopically with fine forceps under anesthesia. Additional flushing is often necessary to dislodge deeply embedded particles. If a foreign body remains undetected, it can migrate for weeks and cause chronic inflammatory conditions and abscesses.
9. What role do teeth play in chronic rhinitis?
Periodontitis of the maxillary canine teeth, in particular, can lead to oronasal fistulas and chronic rhinitis. A thorough dental examination with dental X-rays should be performed for any chronic unilateral rhinitis. Treatment of the dental disease is then crucial.
10. What is the prognosis?
Acute rhinitis of infectious origin usually heals well. Aspergillosis heals after topical therapy in about 80 percent of cases if bone lysis is not too extensive. Chronic idiopathic rhinitis often requires lifelong treatment. Tumor-related forms have a more guarded prognosis, which varies depending on the tumor type.

Literature

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  • Windsor, R. C., & Johnson, L. R. (2006). Canine chronic inflammatory rhinitis. Clinical Techniques in Small Animal Practice, 21(2), 76–81. https://doi.org/10.1053/j.ctsap.2005.12.014
  • Meler, E., Dunn, M., & Lécuyer, M. (2008). A retrospective study of canine persistent nasal disease: 80 cases (1998–2003). The Canadian Veterinary Journal, 49(1), 71–76.
  • Saunders, J. H., Van Bree, H., Gielen, I., & De Rooster, H. (2003). Diagnostic value of computed tomography in dogs with chronic nasal disease. Veterinary Radiology & Ultrasound, 44(4), 409–413. https://doi.org/10.1111/j.1740-8261.2003.tb00477.x
  • Lefebvre, J., Kuehn, N. F., & Wortinger, A. (2005). Computed tomography as an aid in the diagnosis of chronic nasal disease in dogs. Journal of Small Animal Practice, 46(6), 280–285. https://doi.org/10.1111/j.1748-5827.2005.tb00321.x
  • Sharman, M. J., & Mansfield, C. S. (2012). Sinonasal aspergillosis in dogs: A review. Journal of Small Animal Practice, 53(8), 434–444. https://doi.org/10.1111/j.1748-5827.2012.01245.x
  • Prior, C., Swales, H., Sharman, M., Reed, N., Bommer, N., Kent, A., Glanemann, B., Clarke, K., Kortum, A., Kelly, D., et al. (2024). Diagnostic findings in sinonasal aspergillosis in dogs in the United Kingdom: 475 cases (2011–2021). Journal of Small Animal Practice, 65(8), 622–630. https://doi.org/10.1111/jsap.13736
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