Symptom guide

Why Is My Cat Sneezing? Cat Flu and Other Causes

Most sneezing cats have an upper respiratory infection (cat flu). Signs, home care, why cats with blocked noses stop eating, and when to see a vet.

Updated October 2026 · 7 min read · By the Hushku editorial team · 3 sources

See a vet within 24 hours. Vet within a day or two; sooner if not eating

Short answer

A sneezing cat most often has an upper respiratory infection (cat flu), usually caused by feline herpesvirus or calicivirus. Mild cases in adult cats that are still eating often clear in 7 to 10 days with supportive care. See a vet if your cat stops eating, has thick discharge, sore eyes, mouth ulcers or a fever, or if it's a kitten. Breathing faster than 35 breaths a minute at rest, or with the mouth open, is an emergency.

Key facts

Most sneezing cats have cat flu, usually herpesvirus or calicivirus.
Up to 80% of cats exposed to herpesvirus stay infected for life.
A cat breathing over 35 breaths a minute at rest needs a vet.
Cats with blocked noses often stop eating; warm, smelly food helps.

This guide is general information, not a diagnosis. If your pet seems unwell, or you're worried, call your vet.

Overview

The occasional sneeze is normal. Repeated sneezing, especially with runny eyes or nose, usually means a respiratory infection, which is very common in kittens, shelter cats and multi-cat homes.

Cornell Feline Health Center notes that feline herpesvirus causes lifelong infection in up to 80% of exposed cats, and up to 45% shed the virus again from time to time, usually when stressed. That's why some cats get "flare-ups" of sneezing and sore eyes after a house move, boarding or a new pet.

Why sneezing cats stop eating: cats rely heavily on smell to want to eat. A blocked nose can stop a cat eating altogether, and cats that don't eat for more than a day or two risk serious liver disease (hepatic lipidosis).

Go to a vet now if you see

Breathing faster than about 35 breaths per minute at rest, open-mouth breathing or effortful breathing
Blue or grey gums
Not eating for more than 24 hours, or a kitten not eating at all
A very sick, lethargic or dehydrated kitten

Common causes

1. Feline herpesvirus
Needs a vet
Sneezing, nasal discharge, and red, runny or ulcerated eyes. Recurring flare-ups with stress are common.
2. Feline calicivirus
Needs a vet
Sneezing and discharge, often with painful mouth ulcers, drooling and sometimes limping in kittens.
3. Bacterial infections (Chlamydia, Bordetella)
Needs a vet
Often with conjunctivitis or coughing, and more common in multi-cat homes and shelters.
4. Irritants
Usually mild
Dusty litter, perfume, smoke, cleaning products and pollen can trigger sneezing without other signs.
5. Chronic rhinitis
Needs a vet
Long-term nasal inflammation, often after a bad bout of cat flu, causing ongoing sneezing and snuffles.
6. Nasopharyngeal polyps
Needs a vet
Benign growths in young cats that cause noisy breathing, snoring and sometimes ear problems.
7. Dental disease, fungal infection or nasal tumours
Serious
One-sided discharge, nosebleeds or facial swelling, especially in older cats.

What you can do at home

Gently wipe discharge from the eyes and nose with cotton wool dampened with warm water.
Sit your cat in a steamy bathroom for 10 to 15 minutes to loosen congestion (never leave it unattended).
Offer strong-smelling, slightly warmed wet food to tempt the appetite.
Keep sick cats separate from other cats and wash hands between them.
Don't give lysine on its own as a treatment: Cornell notes studies suggest it's not effective.
Never give human cold or flu medicines; paracetamol (acetaminophen) is deadly to cats.

When to see a vet

Sneezing with thick yellow or green discharge, sore eyes or mouth ulcers
Not eating, drooling or lethargy
Sneezing lasting more than a week or keeps coming back
Any sneezing kitten, older cat or cat with other health problems
Nosebleeds or discharge from one nostril only

Prevention

Keep FVRCP vaccines up to date; they reduce how severe cat flu is
Reduce stress for cats known to carry herpesvirus
Isolate new cats for a week or two before introductions
Use low-dust litter

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Sources

We check guides against veterinary sources and update them when guidance changes. How we write and review.

Questions.

Can I catch a cold from my cat?

No. Cat flu viruses don't infect people. Bordetella can, very rarely, infect people with weakened immune systems.

My vaccinated cat has cat flu. Why?

Vaccines reduce severity but don't prevent infection in every case, and they don't stop cats that already carry herpesvirus from having flare-ups.

Do sneezing cats need antibiotics?

Most cat flu is viral, so antibiotics don't help unless there's a secondary bacterial infection, such as thick coloured discharge. Your vet will decide.

Key facts

Overview

Go to a vet now if you see

Common causes

1. Feline herpesvirus

2. Feline calicivirus

3. Bacterial infections (Chlamydia, Bordetella)

4. Irritants

5. Chronic rhinitis

6. Nasopharyngeal polyps

7. Dental disease, fungal infection or nasal tumours