What causes bad breath in cats

If your cat’s breath smells bad, you might have more of a problem on your hands than putting up with a foul smell. If you’re noticing your cat’s breath producing a strong, unpleasant odour, this isn’t normal and warrants further investigation. Ongoing bad breath in a cat can be due to a variety of health problems. In fact, around 75 per cent of cats over the age of three have dental disease, and smelly breath is usually one of the first signs pet owners notice.
Cat breath

Dental disease

Odour-producing bacteria building up in your cat’s mouth will most likely be the cause of your cat’s bad breath. Saliva and bacteria form plaque that can then mineralise and become tartar if not treated. This can lead to periodontal disease that is an infection of the supporting tissues of the teeth. Excessive brownish tartar, drooling, difficulty eating or favouring one side when chewing, plus inflamed gums are signs that your cat has dental disease that should be addressed by your vet.


Dietary issues can contribute to bad smelling breath with foods such as fish or liver based ingredients contributing to the smell. Cats may also accidently chew on foreign objects like rubber bands resulting in particles becoming lodged in their mouth. This is an easy problem to solve though. All you need to do is change what you feed them.

Gingivitis and Stomatitis

Gingivitis is an inflammation of the gums. Stomatitis is an inflammation of the mucous linings of the mouth. Cats are prone to developing these conditions, usually due to dental disease, but sometimes due to other bacteria, viruses or allergies. Your vet can advise you if your cat needs further testing to check for infections such as FIV and Calicivirus.

Metabolic diseases

Sometimes bad breath is more than just poor oral hygiene. In certain, less common cases it can be a red flag to more serious internal conditions such as kidney disease, particularly in elderly cats. A build-up of toxins in the blood can lead to bad breath, as your cat’s kidneys become overwhelmed and are unable to detoxify effectively anymore. Other conditions which could cause bad breath include diabetes and liver disease. If you have concerns, a simple trip to the vet is the best way to check your cat’s health.

How to treat bad breath in cats

The first thing to do if you notice that your cat has persistent bad breath is to book an appointment with your vet. There are so many potential causes of this symptom: you will save yourself a lot of time, effort, distress and money by having your vet give you the proper diagnosis and course of action early, and if your cat has a serious problem, you’ll help improve their quality of life.

However, most likely your vet will discover a minor problem and treatment will involve little more than a thorough dental cleaning and giving your cat a diet that helps prevent dental disease. ROYAL CANIN®’s Dental Diet contains both a nutrient that reduces tartar build up and a specially designed kibble texture that has a brushing effect on the teeth.

Preventing bad breath in cats

The best way to deal with a problem like bad breath is to treat the problem before it begins. Most oral hygiene issues in your cat can be solved by keeping your cat’s teeth clean, and just like with us, the best way to do that is to brush their teeth. It helps to remove plaque before it has time to properly form on the teeth and reduces the occurrence of gum inflammation.

Many cats will allow you to brush their teeth – especially if you start them young. Your vet will have great advice on what equipment and products to use, but one thing to remember is that you should never use your own toothpaste on your cat. Cats normally will respond badly to the flavour and the ingredients may upset their digestion.

When you start training your cat, let them lick the feline toothpaste off your finger. Once they’re happy to do that, start to hold their lip up as they lick. When they’re comfortable with that, start to touch their teeth with the brush and reward them with a treat. Do this for short periods of time at first, but build up every time until your cat will let you start brushing their teeth.

If you’d like another way to help keep your cat’s teeth healthy, talk to your vet about using an oral health diet like ROYAL CANIN®’s dental range. It has a combined mechanical and nutritional action to help prevent tartar from building up on your cat’s teeth and help keep them in the best dental health. 

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