There are my reasons why your senior cat's breath starts to smell as they age.

Why does my senior cat’s breath smell so bad?

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Due to better nutrition, veterinary and home care, cats are living much longer now than was the case 20 years ago. Cats are considered to be elderly once they reach 11 years with the definition of senior cats defined as those aged between 11 to 14 years and super seniors as 15 years and upwards. With the increasing age of the average cat, many changes in cat’s physiology, behavior and vulnerability to particular illnesses are observed. Many physiological changes include reduced ability to smell and taste food, reduced digestibility, and reduced hearing and immune function, skin elasticity, and stress tolerance. Another common issue pet parents might observe is their cat’s breath becoming stinkier.

Stinky breath in senior cats can be caused by a number of problems – some more serious than others. If you ever notice that your cat is producing strong, unpleasant odor, it’s not normal and you need to visit a vet on immediately. Below you’ll see a list of the most common issues that cause smelly breath in cats.

Common medical issues that cause bad breath in senior cats

Dental diseases

Several bacteria responsible for building up the bad odor might build up in the cat’s mouth and can cause bad breath. The plaque formed due to saliva and bacteria in the mouth, which can then mineralize and become tartar if not treated. This infection can lead to periodontal disease –  an infection of supporting tissue of teeth. Tartar buildup, drooling from the mouth, difficulty eating and preferring one side only while eating food are telltale signs of dental infections and should be addressed by your vet. About 50-90% of cats older than four years suffer from some form of dental issues. Appropriate preventive dental care and monitoring are essential for these diseases.

Dental disease prevention and treatment

The best way to treat this disorder is to regularly remove the plaque build-up by the tooth brushing. Use specific toothpaste or gels designed for cats only, because the products designed for humans can be dangerous in terms of toxins for cats. Some cats require a gradual introduction to this brushing and can eventually be trained to accept the preventative measures. If the cat is suffering from gingivitis, the process of brushing can be quite painful, so it’s best to consult a veterinarian before considering the teeth of a cat with gingivitis. Additional treatments, such as professional dental cleanings, may be required if your cat has more advanced gingivitis or tooth decay. Once the damage gets to be too much, some cats might need tooth extractions in order to treat their dental damage.

A few of my favorite kinds of cat toothpaste include the following:

Your cat’s diet

The diet of your cat can contribute to bad-smelling breath from food. Fish and other meat left on the teeth can start to rot, and therefore cause bad breath. This is more of a problem if your cat primarily eats wet food – dry food actually cleans the teeth. So, to avoid this problem all you need is to change the diet of your cat.

Another common cause of bad breath is something caught in your cat’s teeth or under the gums. When the cat eats its food, the strands of the meat or other food particles might catch in your cat’s teeth or under the gums. The food or the strand of hair or string, for example, can get lodged in the nooks of the crannies between teeth and can decompose resulting in damaged tissue.

How you can change your cat’s diet to prevent bad breath

Avoid cheap cat foods – using high-quality cat foods will help to offer a solution. A variety of oral care cat food is available in the market and is uniquely shaped and textured kibble that scrubs the cat teeth while chewing. The rubbing action cleans the tartar and plaque and prevents the development of bacteria responsible for the foul mouth odor. Any sudden unpleasant change in breath smell warrants a trip to the vet and perhaps talking to them about diet changes.

As mentioned earlier, cleaning your cat’s teeth using a specialty cat toothpaste on your finger can also help with this issue. It will remove leftover food particles stuck to the teeth.

Metabolic diseases

Sometimes the bad breathing problem is not just about oral hygiene. Sometimes the serious internal conditions like kidney diseases could be the reason for bad breath. The toxins in the blood lead to the development of bad breath as the kidney becomes overwhelmed and becomes unable to detoxify the toxins effectively anymore. Other conditions that contribute to bad breath include diabetes and liver diseases.

Metabolic disease prevention and treatment

If you suspect any problem in your cat, a simple trip to the vet is the best way to check your cat for any infections. An overall health profile of your pet will help you to identify any internal problem including metabolic disorders.

Lymphocytic Plasmocytic Stomatitis

In some cases, the bad breath is caused by a condition termed as lymphocytic plasmocytic stomatitis. This condition is associated with leukemia virus, calicivirus, Bartonella, feline immunodeficiency virus, and other infections. It is a serious inflammation of the mouth that causes odors and extreme pain. The cat’s gums will become sore, swollen, and bleed, and it typically hurts when they open their mouth. Again, the treatment involves cleaning and removing some or all the teeth along with the antibiotics. In addition to gingivitis and stomatitis, cats with the feline calicivirus suffer from upper respiratory infections characterized by discharge from the eyes, runny nose, sneezing, and ulcers on the tongue.

Lymphocytic Plasmocytic Stomatitis Prevention

The calicivirus vaccine is recommended and protects from getting this disease. The calicivirus is transmissible to other cats and is common in places with high concentrations of cats. It’s important to keep the cats up to date on vaccines.

Mouth cancer

Cancer in the oral cavity can contribute to foul odors because the tumor grows and become infected and cause halitosis. When a cat is diagnosed with squamous carcinoma, the prognosis is not good, and cats usually only live 2-6 more months.

Mouth cancer treatment

Removal of the tumor through surgery by an expert veterinarian is the primary treatment here. Your vet may also suggest chemotherapy and radiation if they feel like your cat will benefit from it. In most cases, vets will feel like those treatments will not extend your cat’s life very long, and will usually decide against it.

Kidney disorders

If the cat’s breath smells like ammonia or urine, this could be a kidney disease which is common in cats with 8 years or older age. Cats with kidney disorders appear lethargic and may experience weight loss, drink more water and urinate as frequently and in greater volume. The bad breath is an indication of toxins building up in the body.

Feline kidney disorder treatment

Visit your vet for a proper examination of your cat, blood tests and urinalysis will be done if kidney problem is suspected by the vet. To manage the kidney disorders, dietary modifications like cutting off the phosphorous content of the food or minimizing it are done. Make sure your cat is well hydrated and keep a check on the secondary issues like anemia or high blood pressure.

Feline liver disorders

Along with the irritating smell of a cat’s bad breath, yellowing of the white part of the eyes is an indication of liver disease. Other symptoms include yellowing of skin on the ears or on the gums, becoming lethargic, a loss of appetite or have very poor one, along with diarrhea and vomiting. Liver disease causes cats to urinate more frequently and as a result, they will drink more and more water.

Feline liver disorder treatment

Consult your vet, because the treatment varies and depends on the cause of liver disease. The complete health history of the cat along with the physical examination will be considered by the vet. If the origin is not obvious, the underlying problem by running blood work, urinalysis, and other tests might be done.


Is bad breath a common issue in aging cats?

According to the International Cat Care, 85% of cats have some sort of dental diseases. Other conditions related to bad breath are respiratory disorders, diabetes, skin diseases or oral trauma like electric cord injury. The most common problem associated with bad breath is periodontal disease. If you ignore the oral hygiene for your cat, the disease is likely to cause pain, tooth loss, infection, and in some cases can spread to organs. Gingivitis is swelling of gums that result in tissue and bone loss. It can be remedied with professional teeth cleaning to give a fresh start to your cat, but plaque can again develop within days without regular tooth brushing. Bad breath sometimes indicates serious conditions like diabetes (if it is sweet) or kidney infections (if it smells like urine), or it can be a sign of liver and intestinal blockage (if it’s generally foul). Bad breath can also be a sign of mouth ulcers, sores or even cancer.

How can I avoid bad breath in my cats?

Brush your cat’s teeth every day, just before any treat you can take a tiny amount of the gel onto the finger and gently apply it to the cat’s teeth. Once the cat is tolerant to the gel on the finger prior to receiving the cherished item, try the same routine with the gel on the brush rather than the fingers.

What if these methods aren’t working?

If your cat has persistent bad breath, book an appointment to the vet. A vet can guide better and will prescribe the best diagnosis, course of action early and if the problem is serious will help you to improve the situation. This will save a lot of time, effort, distress, and money. Most likely the vet can detect minor problems and treatment involves little more than a thorough dental cleaning and may suggest a diet plan that helps to prevent dental diseases, but as discussed earlier, the best way to deal with the problem is to treat the problem before it begins. Your vet will have great advice on what equipment and products to use.

As a general rule, the healthy cat’s breath doesn’t have much of a smell and certainly not something you’d readily describe as an odor. Smelling like food is one thing, smelling like decay is another. Consistency is important, if the breath smelled one way and you suddenly notice it now smells a little different, that’s the reason to contact your vet. Your feline might need an antibiotic to clear up the infection or some diagnostic testing to check internal disorders. As with any sudden change, you should call your vet right away if your cat’s breath suddenly smells really bad. The sooner you get to the root cause, the better.

2 Replies to “Why does my senior cat’s breath smell so bad?”

  1. Abbi Marson says:

    My cat will be 15years old this year and has awful bad breath, especially noticeable when she is washing herself. I have taken her to the vets who said they couldn’t find anything obviously wrong, there is a little bit of tartar build up on her back teeth but she said it wasn’t enough to warrant putting her under anesthetic to clean them. I have tried brushing her teeth but she hates it and claws me, I have also tried using colloidal silver in her mouth but nothing works. Her diet is dry biscuits (Purina Sensitive), apart from a bit of raw meat occasionally. Can you give any other advice please.

    1. patricia jackson says:

      My elder cat also has terrible breath. A few years ago he had major dental surgery, but now that he is 18 I do not want to put him under the stress of that surgery again. His recent bloodwork reveals he has no disease. I don’t know what to do.

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