Nasal Discharge, Bloody Nose and Sneezing in Dogs — It “Snot” Normal

Our furry friends, with their wagging tails and wet noses, bring immense joy to our lives. But what happens when that adorable wet nose turns into a runny faucet? This blog delves into nasal discharge in dogs, discussing its causes, treatments, and the crucial role of specialized medical tests like rhinoscopy.

Normal Nasal Moisture

Dogs normally have moisture in their nasal passages, and this can even be seen as moisture on the nose and around the nostrils, the so-called “wet nose”. This moisture serves several essential functions:

1. Moistening and Protection: The nasal mucosa produces mucus to keep the nasal passages moist and prevent them from drying out. This moisture helps trap dust, debris, and potential pathogens.
2. Olfaction Enhancement: Dogs rely heavily on their sense of smell. The thin layer of mucus over the olfactory epithelium enhances the detection of scent molecules.
3. Immune Defense: The mucus is a barrier to help prevent infections.

Common Causes of Nasal Discharge

1. Allergies: Dogs can develop allergies to environmental factors (pollen, dust, mold) or certain foods. Allergic reactions lead to clear nasal discharge, sneezing, and itching.
   Treatment involves identifying triggers and managing symptoms. In addition, newer specific canine allergies medications are available that may help to improve allergic nasal symptoms.
2. Infections: Bacterial, viral, parasitic and fungal infections can cause nasal discharge. Signs include thick mucus, bad breath, and sometimes fever. Specific treatment depends on the type of infection. For bacterial infections, it is important to remember that bacteria normally inhabit the nasal passages, and in order for bacteria to establish an infection, some other problem almost always precedes this. Therefore, bacterial infections are almost always secondary to an inciting cause. Antibiotics may temporarily improve the nasal discharge, but once they are stopped, the symptoms typically return. 
3. Foreign Objects: Grass, plant material, food or other objects can get lodged in the nasal passages. Frequent, excessive sneezing, pawing at the nose/face and unilateral discharge (from one nostril) may indicate a foreign body. We use rhinoscopy to identify these objects and remove them without the need for surgery.
4. Dental Issues: Infected teeth, gum disease, or tooth root abscesses can lead to nasal discharge. The roots of the upper teeth can become diseased and erode into the nasal cavity (oronasal fistula) allowing food and water to enter the nasal cavity from the mouth. Foul-smelling breath often accompanies dental problems. A thorough dental examination (often with dental X-rays) is needed to identify these problems.
5. Tumors and Polyps: Nasal tumors (cancerous) or polyps (benign) obstruct airflow and cause discharge. Other signs may include noisy breathing, snoring, bloody nose and facial or nasal swelling. Diagnosis involves rhinoscopy for visual inspection and biopsies, and sometimes imaging (X-rays, CT scan).
6. Idiopathic Lymphoplasmacytic Rhinitis: This is a chronic inflammatory disease of the inside of the nasal cavity of unknown cause (idiopathic). Chronic sneezing and nasal discharge is typically frequent. This condition may be due to an abnormal immune response to inhaled allergens, bacteria or viruses. Persistent, long-term nasal passage inflammation can lead to erosion and destruction of the mucosa (lining of the nose) and underlying nasal turbinates (nasal bones), leading to bloody nasal discharge (epistaxis).