TL;DR: Yellow nasal discharge from one nostril usually indicates a localized infection or foreign object and requires a veterinary visit within 24-48 hours. Seek emergency care immediately if your cat has trouble breathing, facial swelling, or stops eating.
What does it mean if my cat has yellow nasal discharge from one nostril?
Yellow mucus is typically purulent discharge, meaning white blood cells are responding to an underlying issue. When limited to one nostril, common causes include:
- A foreign object stuck in the nasal passage
- A tooth root abscess that has moved into the sinus
- A nasal polyp
- A localized fungal or bacterial infection
Is yellow nasal discharge in cats considered a veterinary emergency?
While the urgency level for yellow mucus from one nostril is generally medium, certain symptoms require more immediate attention:
- Within 24 to 48 hours: Schedule a veterinary exam to prevent chronic inflammation from causing permanent damage to the nasal turbinates.
- Immediate Care: Seek veterinary help urgently if your cat is experiencing extreme difficulty breathing, refuses to eat, or has significant facial swelling.
Why should I take a photo of my cat's nasal discharge for the vet?
Capturing a clear, well-lit photograph of the discharge can be incredibly helpful for your veterinarian for several reasons:
- Nasal discharge can be intermittent and may be groomed away before you arrive at the clinic.
- A photo allows the vet to see the exact color, consistency, and volume of the mucus.
- It provides vital clues for triage and helps determine which diagnostic tests, such as X-rays or nasal swabs, are most appropriate.
Clinical Context (Merck Veterinary Manual)
In cats, a unilateral nasal discharge, especially if acute and accompanied by pawing at the face, may indicate a foreign body. Chronic nasal discharge, initially unilateral but becoming bilateral or changing in character (e.g., mucopurulent to serosanguineous or hemorrhagic), suggests neoplasia or mycotic disease. Chronic rhinosinusitis, a frequent sequela of acute viral infections, can also result in yellow mucus. Fungal rhinosinusitis, particularly Cryptococcus, is more common in cats than dogs. Diagnosis involves history, physical examination, advanced imaging (CT), rhinoscopy, nasal biopsy, and deep nasal tissue culture to rule out other causes and identify a specific etiology.
Chapter: Respiratory, Infectious Diseases, Neoplasia, Fungal
Source: The Merck Veterinary Manual, 11th Edition (Page 1489)