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Chronic Kidney Disease in Cats


Chronic renal disease is one of the most common debilitating diseases of senior cats. It is the end result of various ageing and disease processes that cause, along with other health problems, inflammation of the kidneys. 

The disease is insidious as signs of kidney failure only appear when about two thirds of the kidney cells are not functioning. Failing kidneys cause imbalances in body water, electrolytes and waste products: the kidneys become unable to conserve urine or proteins, and allow waste products such as urea to build up in the bloodstream. The increased urine loss causes dehydration and thirst.

This results in the first symptoms of kidney disease – excessive drinking and the passing of large volumes of urine. Despite frequent drinking, the pet can still become dehydrated.

The loss of protein in the urine causes malnourishment and affected cats lose weight. Other symptoms include anaemia (healthy kidneys are critical for red blood cell production), poor appetite, mouth ulceration, bad breath and vomiting.

While chronic progressive renal disease can’t be cured, cats can remain quite healthy for considerable periods if care is taken with their diet, fluid intake and general comfort.


The symptoms described above are a good indicator of chronic renal disease but other disease processes need to be ruled out. For example, cats with diabetes or thyroid disease also drink and urinate excessively, and urine can develop high levels of protein in cases of acute renal disease caused by toxins. Blood and urine testing – done in house at CVH – are important diagnostic tools that can help us pinpoint the cause of these symptoms.


Although most cases of degenerative kidney disease are incurable, careful medical management, avoidance of stress and good home nursing can give affected cats a longer, high quality life. We can also report that kidney transplants in cats have been successfully carried out by Australian veterinary specialist surgeons.

The aims of treatment are to:

  • maintain a good urine output
  • reduce the work load of the kidneys and,
  • replace those substances that are being lost in the urine.

The good news is that there are now medications available to help manage chronic renal disease. These act by increasing the blood flow to the kidneys, helping the body eliminate waste products and – as pets with chronic kidney disease often have high blood pressure – helping to maintain correct blood pressure.

Once stabilised with veterinary treatment (this may require intravenous fluids, for example), dietary management at home is very important. The aim is to feed a kidney-supportive diet that is high in carbohydrates and fat, and low in protein.

The easiest and most effective way you can ensure your pet receives a diet nutritionally balanced for chronic renal disease is to feed a commercial feline kidney prescription diet. CVH stocks a high quality range of these excellent science diets.

One thing that’s important to note is that when it comes to diet, dogs and cats are quite different (which is why the feline prescription diets are so effective).

For example, it’s safe to feed dogs with kidney disease a low protein diet, but cats have much higher protein requirements – and low protein diets are unpalatable to cats. The compromise is to feed as much high quality protein as possible. The large size of protein molecules makes the kidneys work too hard and red meat is especially hard to process. Safer protein-rich foods include white meats such as chicken (and most cats adore rabbit meat), cooked eggs and small amounts of liver.

A high level of animal fat is needed to supply energy for maintaining body weight and to increase the diet’s palatability. Weigh your cat regularly to monitor whether your pet’s diet is adequate for weight maintenance. We may also recommend supplementing with water soluble vitamins B and C.

Most importantly, to maintain a good urine flow and at the same time prevent dehydration, unlimited fresh water must always be available.

Three to four small meals each day is better than 2 larger meals. This enables the kidneys to more easily handle waste excretion, and your cat will be more likely to finish each meal.

Avoid stress! Cats with kidney disease are usually old as well as sick. Any form of stress – for example, a new pet in the household, or a cold sleeping place – can exacerbate the condition. Lots of TLC and special care really do help.