Why Is My Cat Sneezing? Causes, Treatment & When to See a Vet

An occasional sneeze in a cat is completely normal, just like in humans. A bit of dust, a strong smell, or a tickle in the nose can all trigger a single sneeze. But persistent, frequent sneezing, or sneezing accompanied by other symptoms like nasal discharge, watery eyes, or lethargy, signals that something needs investigating.

As a vet, I see sneezing cats regularly, and the cause ranges from mild, self-limiting viral infections to chronic conditions requiring long-term management. The key is knowing the difference between a benign sneeze and something that warrants veterinary attention.

This guide covers every common cause of sneezing in cats, what to watch for, and when to call your vet.

Is It Normal for Cats to Sneeze?

Yes, occasional sneezing is normal. Cats sneeze to clear their nasal passages of irritants, just like we do. A sneeze here and there, with no other symptoms, is nothing to worry about.

However, sneezing that happens multiple times a day, continues for more than a few days, or is accompanied by nasal discharge, eye discharge, coughing, reduced appetite, or lethargy is not normal and should be checked by a vet.

Common Causes of Cat Sneezing

1. Upper Respiratory Infection (Cat Flu)

Upper respiratory infections, commonly known as cat flu, are the most common cause of sneezing in cats. They're typically caused by feline herpesvirus (FHV-1) or feline calicivirus (FCV), both highly contagious viruses spread through direct contact with infected cats or contaminated surfaces. Symptoms include frequent sneezing, nasal discharge (clear or coloured), watery eyes, conjunctivitis, mouth ulcers, lethargy, and reduced appetite. Kittens, unvaccinated cats, and cats in multi-cat environments are most at risk. Most cases resolve within 7-14 days with supportive care, but some cats become chronic carriers.

2. Bacterial Infections

Secondary bacterial infections often develop on top of viral cat flu, particularly if the immune system is already compromised. Chlamydophila felis and Bordetella bronchiseptica are common culprits. Bacterial infections typically cause thick, coloured nasal discharge (yellow or green), and may require antibiotic treatment.

3. Allergies

Cats can develop allergies to environmental triggers like pollen, dust mites, mould, cigarette smoke, perfumes, or cleaning products. Allergic rhinitis causes sneezing, a runny nose, and watery eyes, but typically without the lethargy or fever seen with infections. Symptoms often come and go seasonally or correlate with exposure to specific triggers.

4. Foreign Body

Grass seeds, plant material, or other small objects can become lodged in a cat's nasal passages, causing violent, sudden-onset sneezing, often one-sided. The cat may paw at their face, sneeze blood, or show distress. This requires veterinary removal, often under sedation.

5. Dental Disease

Severe dental disease, particularly tooth root abscesses involving the upper teeth, can cause sneezing due to the close proximity of tooth roots to the nasal cavity. An infected tooth root can erode into the nasal passage, causing sneezing, nasal discharge, facial swelling, and pain. This requires dental X-rays and treatment, often tooth extraction.

6. Nasal Polyps or Tumours

Growths in the nasal passages, either benign polyps or malignant tumours, cause chronic sneezing, nasal discharge (sometimes bloody), noisy breathing, and facial deformity in advanced cases. These are more common in older cats and require imaging and biopsy for diagnosis. Treatment may involve surgical removal or other interventions depending on the type.

7. Fungal Infections

Cryptococcus is a fungal infection that can affect the nasal passages, causing chronic sneezing, thick nasal discharge, and swelling around the nose. It's relatively rare but more common in immunocompromised cats. Diagnosis requires specific testing, and treatment involves long-term antifungal medication.

8. Irritants

Strong smells, cleaning products, aerosols, dust, cigarette smoke, scented candles, and air fresheners can all irritate a cat's sensitive nasal passages and trigger sneezing. This type of sneezing is usually immediate and stops once the irritant is removed. If your cat sneezes consistently in a particular room or after you clean, consider environmental irritants.

9. Asthma

While asthma primarily affects the lower airways (lungs), it can occasionally cause sneezing alongside its more typical symptoms: coughing, wheezing, and difficulty breathing. Asthma is triggered by allergens and requires specific treatment with bronchodilators and corticosteroids.

10. Chronic Rhinitis

Some cats develop chronic inflammation of the nasal passages, often following severe cat flu as kittens. This causes persistent sneezing, nasal discharge, and congestion that never fully resolves. Management focuses on supportive care, steam therapy, and sometimes anti-inflammatory medication.

Other Symptoms to Watch For

Sneezing rarely occurs in isolation. Look for:

• Nasal discharge: Clear (usually viral), yellow or green (bacterial), bloody (foreign body, tumour, or severe infection)
• Eye discharge or conjunctivitis: Red, swollen, or weepy eyes
• Reduced appetite: Cats rely heavily on smell to identify food; a blocked nose often means they won't eat. See our guide on why cats stop eating
• Lethargy or hiding
• Mouth ulcers or drooling
• Coughing or difficulty breathing
• Facial swelling or pawing at the face

For more on recognising illness, read our guide on cat symptoms and when to act.

When Is Cat Sneezing an Emergency?

Seek emergency veterinary care if your cat:

• Is struggling to breathe or breathing through their mouth
• Has severe nasal bleeding that won't stop
• Is collapsed or unresponsive
• Has not eaten or drunk for more than 24 hours
• Is showing signs of severe distress: pawing at face, crying out, pacing

For more on emergencies, read our guide on cat medical emergencies.

When Should I Call the Vet (Non-Emergency)?

Contact your vet within 24-48 hours if your cat:

• Has been sneezing frequently for more than 2-3 days
• Has nasal discharge (particularly if coloured or bloody)
• Has watery or gunky eyes
• Is not eating or is eating less than usual
• Seems lethargic or unwell
• Is sneezing blood
• Is a kitten: young cats deteriorate faster

Home Treatment for Mild Cat Sneezing

If your cat has mild sneezing with no other symptoms and is eating, drinking, and behaving normally, you can monitor at home for 24-48 hours:

• Steam therapy: Run a hot shower and sit with your cat in the steamy bathroom for 10-15 minutes to help clear nasal congestion (don't put them in the shower)
• Gently clean discharge: Use a warm, damp cloth to wipe away nasal and eye discharge
• Encourage eating: Warm wet food to enhance the smell; if their nose is blocked, they may not eat. For more tips, see our guide on encouraging cats to eat
• Remove irritants: Avoid aerosols, strong-smelling cleaning products, and cigarette smoke
• Monitor closely: If symptoms worsen or don't improve within 48 hours, see your vet

Do not give human cold or flu medications to cats they are toxic.

How Is Cat Sneezing Diagnosed?

Your vet will start with a thorough physical examination, checking the nose, mouth, throat, and eyes. Depending on what they find, they may recommend:

• Nasal swabs or PCR testing: To identify viral or bacterial infections
• Blood tests: To check overall health and immune function
• Dental X-rays: If dental disease is suspected
• Imaging (CT or MRI): To look for polyps, tumours, or foreign bodies
• Rhinoscopy: A camera inserted into the nasal passages to visualise abnormalities
• Biopsy: If a mass or growth is identified

Treatment for Cat Sneezing

Treatment depends on the underlying cause:

• Viral cat flu: Supportive care (fluids, nutritional support, steam therapy), sometimes antiviral medication
• Bacterial infection: Antibiotics
• Allergies: Antihistamines, corticosteroids, allergen avoidance
• Foreign body: Removal under sedation or anaesthesia
• Dental disease: Dental cleaning, tooth extraction if needed
• Polyps or tumours: Surgical removal, chemotherapy, or radiation depending on type
• Chronic rhinitis: Long-term supportive care, anti-inflammatories

How to Prevent Respiratory Infections in Cats

• Keep vaccinations up to date: Core vaccines protect against feline herpesvirus and calicivirus
• Reduce stress: Stress weakens the immune system and can reactivate latent herpesvirus
• Isolate new cats: Quarantine new arrivals for 10-14 days before introducing them to resident cats
• Maintain good hygiene: Wash hands, clean food bowls, and disinfect surfaces regularly in multi-cat homes
• Avoid irritants: Minimise exposure to smoke, strong perfumes, and harsh cleaning products

Can Litter Sense Help?

While Litter Sense doesn't directly detect respiratory issues, some systemic infections and chronic illnesses that cause sneezing also affect the kidneys or urinary system. By monitoring your cat's urine daily, Litter Sense can flag early changes that suggest your cat's overall health is declining, prompting you to seek veterinary care sooner.

To learn more, read our complete guide on how Litter Sense works.

Frequently Asked Questions

Can cat sneezing be serious?

Yes. While occasional sneezing is normal, persistent sneezing can indicate infections, dental disease, foreign bodies, or even tumours. Any cat sneezing frequently for more than a few days should be checked by a vet.

Is cat flu contagious to humans?

No. Feline herpesvirus and calicivirus only affect cats. They cannot be transmitted to humans or other species. However, humans can carry the virus on their hands or clothing and spread it between cats.

How long does cat flu last?

Most cases of uncomplicated cat flu resolve within 7-14 days with supportive care. Severe cases, particularly in kittens or immunocompromised cats, can take longer and may require veterinary intervention. Some cats become chronic carriers and experience recurrent flare-ups throughout their lives.

Why is my cat sneezing but seems fine otherwise?

Mild environmental irritants, allergies, or the very early stages of an infection can cause sneezing without other symptoms. Monitor for 24-48 hours. If sneezing continues or other symptoms develop, see your vet.

Can indoor cats get cat flu?

Yes. While indoor cats have less exposure, they can still catch cat flu if they come into contact with an infected cat at the vet, cattery, or if a new cat is introduced to the home. Vaccination is important for all cats, indoor or outdoor.

Should I isolate my sneezing cat from other cats?

Yes, if you suspect an infectious cause. Cat flu is highly contagious between cats. Isolate the affected cat in a separate room with their own food, water, and litter tray until symptoms resolve and your vet confirms they're no longer contagious.