Why is my cat's nose runny?
A cat with a runny nose most often has a mild upper respiratory infection, sometimes called cat flu, or is reacting to dust or another irritant in the air. It is rarely an emergency on its own, but discharge that is thick, coloured, one-sided or does not clear up within a few days is worth a vet visit rather than waiting it out.
Usually not urgent
This is common and often manageable at home — but see a vet if it persists, gets worse, or comes with other changes.
The most common causes
Upper respiratory infections, often caused by feline herpesvirus or calicivirus and grouped together as cat flu, are the most frequent cause of a runny nose in cats, particularly in kittens, unvaccinated cats, or those recently in contact with other cats such as at a shelter or cattery. These typically come with sneezing, watery eyes and sometimes a reduced appetite alongside the nasal discharge. Kittens and young cats are more commonly affected than older cats who have already been exposed and built some immunity, though any cat can catch it, particularly around stressful events like a house move or a stay in a cattery.
Environmental irritants such as dusty cat litter, strong cleaning products, smoke or scented candles can also trigger a runny nose without any infection involved, usually alongside sneezing but without the lethargy or appetite changes an infection tends to bring.
Less commonly, dental disease, a foreign body such as a blade of grass caught in the nasal passage, or in older cats a growth in the nose, can cause ongoing or one-sided discharge. These tend to persist rather than clear up on their own, which is one of the clues that something more than a passing irritation is going on. A cat who has previously had cat flu can also become a lifelong carrier, with mild flare-ups triggered later by stress or illness even without any new exposure.
When it is worth seeing a vet
Ring your vet if the discharge is thick, yellow or green, comes from one nostril only, contains any blood, or is accompanied by laboured breathing, a reduced appetite, or your cat seeming generally unwell. Any of these point toward something more than a mild, self-limiting irritation. Noisy or laboured breathing in particular should never be left to see how things go, since it can point toward a more significant chest or airway problem beyond a simple runny nose.
A kitten, an older cat, or a cat with an existing health condition is worth taking seriously sooner rather than later, since they are more likely to deteriorate quickly from what would be a mild infection in an otherwise healthy adult cat. This page cannot tell you what is causing your cat's symptoms; a vet examination is the only reliable way to know that, and this is general information rather than a diagnosis.
What you can do while you keep an eye on things
Gently wipe away any discharge with a damp cloth to keep your cat comfortable, and make sure they can still smell their food, since a blocked nose can put a cat off eating even when nothing else is wrong. Warming wet food slightly can help make the smell more appealing if appetite has dropped.
Reducing dust and strong scents around the home, and keeping litter trays clean with a lower-dust litter, can help if an irritant seems to be the trigger. None of this replaces a vet visit if the discharge does not improve or your cat seems increasingly unwell. Keeping food and water bowls away from a dusty litter tray, and washing bedding regularly, are both small changes that reduce ongoing exposure to whatever might be triggering the irritation.
What can help day to day
A low-dust cat litter is worth considering if you suspect the litter itself is part of what is triggering sneezing and a runny nose, since some clay and scented litters produce more airborne dust than others.
Keeping your cat's general routine calm and comfortable while you watch for improvement, and having a proper litter and grooming setup at home, supports recovery from a mild irritation without pretending to treat an underlying infection, which is a job for your vet. Good general nutrition and access to fresh water support a cat's own recovery from a mild illness, though neither is a substitute for veterinary treatment where an infection genuinely needs it.
What can help
Things we stock that owners commonly use alongside a vet’s advice — not a substitute for it.
Leucillin Antiseptic Skincare Spray for Cats & Dogs
A versatile, alcohol-free antiseptic spray that cleans, soothes, and helps protect your pet's skin from bacteria, viruses, and fungi.
From£7.99
Absorbent Cotton Gauze Swabs for Pets – Pack of 100
Highly absorbent, low-lint cotton gauze swabs produced in clean conditions — a practical first-aid essential available in three size and ply combinations.
From£4.49
3M Synthetic Under Bandage Padding for Pets
A soft, breathable non-woven polyester padding layer designed to protect and cushion beneath bandages on dogs and cats.
From£9.49
Little Friends Trimmed Dried Cuttlefish Bones
Trimmed dried cuttlefish bones for birds, reptiles and small pets, a natural calcium source
£9.99
Common questions
- Is a runny nose an emergency in cats?
- Usually not on its own, but it depends on what comes with it. Thick or coloured discharge, one-sided symptoms, laboured breathing or a cat who seems generally unwell all mean a vet visit is worth arranging promptly rather than waiting.
- Can a cat's runny nose clear up on its own?
- A mild irritation from dust or a similar trigger often does settle once the cause is removed. A viral infection like cat flu can also improve with time and supportive care at home, but persistent or worsening symptoms should always be checked by a vet rather than assumed to be clearing up.
- Is cat flu contagious to other cats?
- Yes, the viruses behind cat flu spread easily between cats, particularly in multi-cat households or places like shelters and catteries. Keeping an affected cat away from others where possible, and speaking to your vet about vaccination status, helps limit the spread.
- Should I clean my cat's nose myself?
- Gently wiping away visible discharge with a damp, clean cloth is fine and helps keep your cat comfortable. Do not attempt to clean inside the nostril itself, and see your vet if discharge keeps building up or looks unusual, rather than trying to manage it entirely at home.
Related
Sources
Written against guidance published by UK veterinary and welfare organisations. Always confirm specifics with your own vet.
Written by Matt Garnett, who runs Giddy Pets and is a lifelong pet owner — not a vet. This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your animal. How we write these guides.