Cats rightly hold a reputation for being fastidious when it comes to personal grooming. It’s therefore only right that their owners should be concerned when they notice unpleasant smells from their cat’s mouth. The reasons this might happen range from straightforward problems such as a stinky new food or teething in young cats, through to more serious and even life-threatening diseases. 

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One of the most common causes of bad breath in middle aged to older cats is dental disease 

Plaque and tartar build up and cause inflammation of the mouth and gums. This leads to growth of bacteria and unpleasant smells. Once thick calcified tartar has formed on teeth, the only way to properly treat the problem is a thorough clean, or descale, under general anaesthetic. Your vet will also take the opportunity to examine your cat’s mouth more thoroughly and remove any damaged or diseased teeth. Once the teeth are clean you can help prevent the problem recurring using specialist foods and treats. However,tThe best way to prevent dental disease is through tooth brushing which many cats can be trained to accept given time and patience.

Another common mouth problem seen in cats that can be a cause of malodour is feline gingivostomatitis complex

This is a severe inflammation of the gums that is not in proportion to the degree of dental disease. It is thought to be triggered in many cases by infection with certain viral diseases. The immune system becomes overly responsive to the presence of even small amounts of plaque on the teeth. The condition is often very painful. Owners may notice dribbling, an inability to groom and reduced appetite in severely affected pets. It is vital that you seek veterinary attention for this debilitating condition. Treatment options include anti-inflammatories and antibiotics, but many cases require extensive dental extractions to control the inflammation and bring relief.

Other mouth problems can also cause smelly breath

Something as simple as food or foreign material stuck in the mouth, often between the teeth, can cause a foetid smell. Your vet may be able to see the problem in the consulting room but often a more thorough examination under anaesthetic will be needed to diagnose the problem and remove the offending object. Similarly wounds in the mouth may become infected and cause an unpleasant odour. A common injury is a laceration to the side of the tongue, often due to fighting with other cats. If it becomes infected this may well need antibiotics and possibly stitching once the infection has cleared.

Eosinophilic granulomas are a disorder specific to cats that can occur in the mouth 

They are seen as raised reddened areas that may look like lumps or ulcers in the mouth or tongue. The inflammation they cause and sometimes secondary infections can cause halitosis. They are thought to be a result of hypersensitivity (allergy) or immune responses, but are quite poorly understood. It can often be hard to differentiate them from more serious conditions such as mouth cancers, and biopsy will often be recommended to confirm the diagnosis.

Sadly, especially in older cats, bad breath can be a sign of a more serious problem

Cats will sometimes develop tumours of the mouth – most commonly a form called squamous cell carcinoma. This is an aggressive and painful tumour that is very hard to treat. Unfortunately they are often advanced by the time they are discovered. Even with a range of treatment options available the prognosis is sadly poor for most affected cats.

Another serious disease of aged felines is kidney disease

Initial clinical signs such as increased water intake and urination and weight loss may be hard to pick up but as the disease progresses, cats can develop “uraemic breath”. This reflects high levels of a chemical called urea in the blood, that would normally be removed by the kidneys. Although kidney disease is not curable it can be very treatable if caught early. So it’s important to consult your vet as soon as you have concerns. Occasionally problems with the guts or lungs may also cause bad breath. But this is less well defined and often other signs will be apparent.

There are lots of possible causes for bad breath in our cat companions. Once the simple causes such as diet or teething have been ruled out, a full examination by your vet is essential to diagnose the problem and recommend the best course of treatment. Many of the underlying causes can be easily treated so there is no need to put up with a pongy pet!

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