An occasional sneeze is as normal for cats as it is for people. But when your cat starts a sneezing jag that lasts for days, or when you notice discharge around the nose and eyes, it's time to look more closely. Sneezing can range from a simple response to dust to a sign of serious respiratory infection or even nasal cancer. Understanding the difference helps you respond appropriately and keep your cat comfortable.

1. Upper Respiratory Infection (Cat Flu) — Most Common

Upper respiratory infections (URIs) are the most frequent cause of sneezing in cats, especially in young cats, rescue cats, or multi-cat households. The feline herpesvirus-1 (FHV-1) and feline calicivirus (FCV) together account for the vast majority of feline URIs. Symptoms include sneezing, watery or colored nasal and ocular discharge, conjunctivitis, lethargy, and reduced appetite. Herpesvirus is a lifelong latent infection — stress can trigger recurrences even in vaccinated cats. Treatment is supportive: steam humidification, nasal saline rinses, appetite stimulation, and antiviral medication (famciclovir) for herpes flares.

2. Environmental Irritants

Cats have sensitive noses and can sneeze in response to common household irritants: cigarette smoke, scented candles, air fresheners, cleaning product fumes, perfume, dusty litter, and even cooking spices. Irritant-triggered sneezing typically resolves quickly once the cat moves away from the source. If sneezing started after a household product change, try eliminating the suspect irritant before assuming illness.

3. Allergies

Environmental allergies in cats more commonly cause skin symptoms than respiratory ones, but some cats do develop allergic rhinitis — sneezing, clear nasal discharge, and itchy eyes in response to pollen, dust mites, or mold. Allergic sneezing is typically seasonal, bilateral (both nostrils), and produces clear discharge without fever or appetite loss. Antihistamines and environmental management (HEPA filters, frequent vacuuming) can help allergic cats.

4. Dental Disease

This cause surprises many cat owners: the roots of the upper canine and premolar teeth sit very close to the nasal cavity. Advanced tooth root abscesses can erode into the nasal passages, causing chronic one-sided nasal discharge and sneezing that doesn't respond to antiviral or antibiotic treatment. If your cat has persistent sneezing with discharge from only one nostril, a dental examination under anesthesia should be on the diagnostic list. Extraction of the affected tooth usually resolves the nasal symptoms.

5. Nasal Polyps or Foreign Bodies

Young cats occasionally develop nasopharyngeal polyps — benign inflammatory growths in the nasal passage or throat that cause chronic sneezing, nasal discharge, and sometimes a snoring sound or breathing difficulty. Foreign bodies (a grass seed, a blade of dry grass) lodged in the nasal passage cause sudden-onset violent sneezing, often with a pawing-at-nose behavior. A vet can examine the nasal passages with an endoscope or under anesthesia and remove the obstruction.

6. Feline Chlamydophilosis

Chlamydophila felis is a bacterial pathogen that predominantly causes conjunctivitis but frequently accompanies sneezing and mild nasal discharge. It's more common in multi-cat environments and young cats. Diagnosis is by PCR testing from conjunctival swabs. Treatment with doxycycline for 4–6 weeks is effective, and the infection responds poorly to many other antibiotics.

7. Nasal Tumors (Older Cats)

In cats over 10 years old, persistent one-sided nasal discharge and sneezing — particularly when blood-tinged and unresponsive to antibiotics — raises concern for nasal lymphoma or nasal adenocarcinoma. These tumors are uncommon but carry a more guarded prognosis. Diagnosis requires CT imaging and biopsy. Radiation therapy can achieve meaningful remission in nasal lymphoma. Any older cat with unilateral, chronic, or blood-tinged nasal discharge needs prompt veterinary evaluation including imaging.

When Is It Just a Normal Sneeze?

A healthy cat that sneezes once or twice, shows no discharge, and continues eating and playing normally has almost certainly just irritated its nose with dust or a strong smell. No action needed beyond observing for a day or two. The situation changes when sneezing is frequent, paired with discharge, or accompanied by any change in eating, energy, or breathing — at that point, a vet call is appropriate.