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What is kidney disease in cats?

Chronic kidney disease (CKD) is defined as any abnormality of one or both kidneys that has been present for several months. It is a common condition, affecting about 1 of every 3 cats.1

Your cat’s kidneys play a vital role in removing metabolic wastes from the bloodstream, regulating fluid and electrolyte balance, producing or activating important hormones and helping control blood pressure. If your cat’s kidneys cannot do their job properly, CKD can eventually lead to life-threatening problems.

Cat on the couch with pet parent

What causes kidney disease in cats?

The cause of CKD in cats often is unknown; however, several factors may be involved that could increase your cat’s risk of developing kidney disease:

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The chance of developing kidney disease greatly increases as cats get older (over 10-15 years of age).

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Foods that are high in phosphorus can accelerate the progression of CKD in cats.

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The risk for CKD may be higher in certain breeds of cats (e.g, Persians).

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Other illnesses and health issues can contribute to the worsening of CKD in cats.

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Any conditions that lead to dehydration (eg, vomiting, diarrhea, shock) can worsen kidney function and contribute to CKD progression.


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Early detection of kidney disease in your cat

Catching CKD before signs become obvious is important since signs do not typically appear until 75% of kidney function has been lost. At 7 years and older, a cat’s kidney disease risk increases, so be sure to get a “senior screening” during their annual check-up. CKD is progressive and irreversible, but your veterinarian can help provide long-term care and show you how to track signs in older cats.


What are the signs of kidney disease in cats?

The signs of early-stage kidney disease are not visible. On diagnosis, CKD has already been present for some time but may be managed with the help of vet-approved cat food for kidney disease. Signs of late-stage kidney disease tend to be similar but are far more noticeable to pet parents.


  • Increased thirst
  • Decreased appetite
  • Increased urine volume
  • Weight loss
  • Poor coat appearance
  • Bad breath or a sore mouth
  • Lethargy or weakness
  • Vomiting and diarrhea
  • Constipation
Cata on hind legs being served food bowl

Nutrition for cats with kidney disease

If your cat has kidney disease, the right nutrition can make a positive impact on their lives. Specially formulated therapeutic foods that contain decreased amounts of phosphorus and highly digestible protein, and increased omega-3 fatty acids from fish oil have been shown to enhance quality and length of life in cats with CKD compared with feeding a typical pet food. Your cat’s appetite may vary over time when they have CKD and offering different forms (dry, stews) and flavors of an appropriate food recommended by your veterinary healthcare team can be very helpful. The single most important thing you can do is make any changes to a new food gradually because some cats need several weeks or longer to get used to a new food.

What about using a homemade diet for cats with kidney disease?

While it has gained some popularity online, using a homemade diet (or a raw diet) for cats with kidney disease requires you to take into account several factors, including contamination risks, balancing nutrients, and the overall cost. When looking into nutritional options for cats with kidney disease, it’s always best to get a specific recommendation from your veterinarian.

Hill’s Pet Care Center

Visit the Hill’s Pet Care Center for more info and articles about how you can help your dog or cat stay healthy

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1Lulich JP, Osborne CA, O’Brien TD, Polzin DJ. Feline renal failure: questions, answers, questions. Compend Contin Educ Pract Vet. 1992;14(2):127–153. Brown SA. Renal dysfunction in small animals. The Merck Veterinary Manual website.