Kidney failure in cats


Kidney problems are relatively common in cats. The prevalence of CKD (renal or kidney failure) ranges from about 1% in young cats right up to 30-50% of cats at 15 years of age. So the older your cat the more chance there is that their kidneys will start to fail. Vets will now often screen older cats for early signs of kidney disease to try and identify those cats at risk of developing full blown renal failure and if your cat becomes unwell later in life it is one of the first conditions they might check for as a cause. Diagnosis is usually by blood tests, tests on urine and sometimes an ultrasound scan.

Some cats are at an increased risk of CKD because of their breed or a congenital condition (one present from birth). Persians, Abyssinians and Siamese cats may all be more prone to developing the condition. Other causes might be a long term infection they have acquired such as a urinary tract infection or infected teeth. Another disease which then affects the kidneys like pancreatitis, diabetes mellitus or hyperthyroidism, or possibly a toxin they have been exposed to, could all also be a factor. In many cases though no obvious cause or trigger will be identified and the CKD is ‘idiopathic’, which is a medical way of saying we don’t know what has caused it. For some cats it just seems to be a feature of getting older.

Kidneys perform a number of important functions in the body. They regulate water levels, making sure water is not wasted and that blood concentration remains constant. They ‘clean’ the blood by removing waste products and putting them in the urine. They also have an effect on red blood cell production, blood pressure and electrolyte levels. So when the kidneys begin to fail there is likely to be a range of different symptoms and not every cat will experience them in the same way.


It is not possible to reverse the changes which happen inside kidneys affected by CKD. The aim of treatment is to try and support the remaining functioning kidney tissue and reduce any unpleasant symptoms which your cat is experiencing. Cats with CKD will often be dehydrated, sometimes significantly, they may also feel nauseous, have a poor appetite and be losing weight. Treatments may well include giving your cat extra fluids to counteract dehydration, giving anti-sickness medications, appetite stimulants, antibiotics or blood pressure medication. The mainstay of long term management is a special diet which aims to modify your cat’s protein intake. Your vet will advise you on which treatments and changes to your cat’s diet are appropriate for your cat.


We can only guess at how a cat feels when they have CKD but since you are likely to know your cat well and have spent a good deal of time with them you are probably the best person to assess how they are doing. As time goes on they might well feel rather like they have a nasty hangover; tired, nauseous, grotty, and with a persistent thirst. Being dehydrated doesn’t feel good and when your body is losing lots of weight that can also be unpleasant. Many people worry about whether their pet is in pain and this can be a hard question to answer, especially in cats who generally play their cards close to their chest and don’t make an outward show of their feelings.

Warning signals that your pet may be in pain and what to do?

Symptoms of kidney failure in cats
Because cats can be quite private and stoical creatures often by the time they are showing any outward signs of kidney problems and are taken to the vet the disease can be quite advanced. The commonest signs they show are drinking more than usual, weight loss and a reduced appetite. They might also be vomiting occasionally, have bad breath or seem rather tired and listless.
Kidney Failure in Cats Life Expectancy (How Long Will My Pet Live?)
Some cats, given the right support and diet, will be able to live with CKD quite successfully and feel relatively healthy. Others, unfortunately, will experience a continuing deterioration in their kidney function and start to feel more unwell for more of the time. Its not always possible to predict in advance which path your cat is going to follow. No two cats are the same or have the same response to the disease and its treatment. Some cats are very resistant to changing their food or hate taking medication, others get very distressed being transported to the vets. Only time, and sometimes a little trial and error, will tell how your cat will do.
Warning signals that your pet may be in pain and what to do?
Its possible that in the later stages of CKD animals do feel pain which may be mixed up with other feelings of extreme lethargy, sickness, depression, all of which adds up to an overall poor quality of life and at some point becomes an unacceptable state of suffering. There is no way of measuring with certainty when this state has been reached, or is about to be reached, but most people agree that we should intervene at, or perhaps preferably, just before this point and consider cat euthanasia.