Cat peeking through the curtain on window sill

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 looking out the window with pet parent

What contributes to 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 & its progression:

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The chance of developing kidney disease increases as cats get older.2

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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, diarrhoea, shock) can worsen kidney function and contribute to CKD progression.


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Early detection of kidney failure 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.2 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 & symptoms 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 its progression can be slowed down with the help of vet-approved cat food for kidney disease. Signs & symptoms 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
  • Bad breath or a sore mouth
  • Lethargy or weakness
  • Vomiting and diarrhoea
  • Constipation
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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 clinical nutrition that contains decreased amounts of phosphorus and highly digestible protein, and increased omega-3 fatty acids from fish oil has been shown to improve 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 flavours of an appropriate food recommended by your veterinary healthcare team can be very helpful. When you make any changes to a new food, it is important so do so gradually because some cats need several weeks or longer to get used to a new food.

Nourish your pet's microbiome

New evidence supports a link between gut health and kidney health.3 Nutrition that is formulated with ingredients shown to nourish the gut microbiome can help reduce waste products that can be harmful to their kidneys.

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 cat stay healthy

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.

2Brown SA. Renal dysfunction in small animals. The Merck Veterinary Manual website. 2013 []

3Hill’s Clinical Evidence Report Nourishing the gut microbiome helps support kidney health in cats and dogs with chronic kidney disease. 2023