Cat swollen bottom lip: what does it mean and how to help

Updated 29/04/2024

Ever seen a cat's swollen bottom lip? This noticeable problem can be caused by allergies, disease, or general cat life. However, whilst it may make them look like they’re pouting, it must always be taken seriously.

Here are a few facts about cat lips, reasons why your cat might have a swollen bottom lip, and what to do if you’re concerned or worried.

Do cats have lips?

Ah, one of life’s most mysterious, most-asked questions: Do cats have lips? Yes, they do. Like us, they’re mammals, and members of the mammal team have lips. They’re super small and mostly hidden by fur, but if you’re curious to see them, ask your vet if they can gently do this for you. Please don’t attempt to open or fiddle with your cat’s mouth without veterinary guidance - it can be distressing for the cat and you could even end up with a nasty bite.

Why is my cat’s bottom lip swollen?

There are a few reasons your cat’s bottom lip is swollen and pink. Whilst we’ll list some of the most common causes of why a cat's bottom lip is swollen, you must visit your vet immediately if you notice any changes in your cat. Our suggestions might help your vet work out why your cat’s bottom lip is swollen, but there could be a range of health or environmental problems that have caused it.

With that in mind, here are some of the most typical reasons for a cat’s swollen lip.

Food allergies

That makes sense, right? If anything is going to cause a cat's lip to swell always look to their food first. Have you recently changed your brand or food type? Perhaps a cat food company has altered their recipe? If you notice your cat’s bottom lip looks swollen and sore immediately investigate their food bowl as soon as you’ve called their vet.

Other allergic reactions

Did you know some cats are allergic to plastic bowls? Or, rather, specific types of plastic bowls. Some kitties are sensitive to certain chemicals found in particular plastics - if you’ve recently changed their food bowl, this could be a possibility.
Other allergic reactions also include seasonal allergies, skin allergies to other chemicals (detergent, perfume), or even allergies to fleas and dust mites. Other symptoms of cat allergic reactions include:

• Sneezing frequently or multiple times in a row
• Obsessively scratching their mouth or chin
• Red spots or hives along their mouth and face
• Watery eyes
• Vomiting and diarrhea 
• Patches of hair loss
• Sore, scabby, flaky, or red skin 

Feline acne

Yep, cat chin acne is a real thing! However, it’s a poorly understood condition in cats, but luckily very treatable. Feline acne occurs when the hair follicle becomes blocked due to excess production of keratin (a protein found in the skin). It has a similar appearance to human acne, except it’s often accompanied by inflation of the chin and bottom lip. Talk to your vet, they’ll be able to prescribe an anti-inflammatory topical treatment to soothe, clean, and heal the area.

A bacterial infection

Cats scrap, they fight, they brawl, it’s upsetting to see but it’s nature. Sadly, these tiffs can leave their marks and even lead to a bacterial infection. If your cat's bottom lip looks swollen, check to see if there are any tell-tale scratches or claw marks. Did you recently hear a cat fight or are they known for cat attacking their fur siblings? Take them straight to your vet to have the wound cleaned and treated, they may even need to prescribe some antibiotics if the injury is infected.

Dental diseases

There are a few types of cat dental disease, the most common are periodontal disease and infected teeth. Periodontal disease can occur at any age and without appropriate management becomes progressively worse over time. An infected tooth can occur if a cat has cracked or damaged a tooth from a fall, a fight, or a foreign object, allowing bacteria into the tooth. Whatever the disease or issue, these will cause noticeable swelling around the cat’s lip and jaw. All dental diseases should be taken seriously as they can prevent your cat from eating and drinking and are also usually quite painful.
Other signs of dental diseases are:

• Excessive drooling
• Bleeding from the mouth, lips, or gums
• Reduced appetite or inability to chew food (particularly dry cat biscuits)
• Pawing at their mouth
• Foul-smelling breath
• Weight loss
• Lethargy or fatigue
• Excessive hiding

Contact your vet immediately if you suspect your kitty has dental disease or is behaving differently.

Meet our veterinary expert, Holly

This article has been checked by veterinarian Holly Anne Hills BVM BVS BVMedSci. After graduating from the University of Nottingham, Holly spent two years working as a farm animal vet. She then spent some time traveling and volunteering in India, working at neutering clinics and with injured street dogs. Holly now works in small animal practice, and balances this with writing, volunteering with the comms team at Vet Sustain, and she is also a marine mammal medic!

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