Black and white cat

Supporting Your Cat's Kidney Health

Your cat’s kidneys are essential in supporting their overall health by filtering and recycling resources for the body. However, sometimes the kidneys may begin to fail, resulting in chronic kidney disease (CKD). The signs are difficult to spot, however as we'll explain, if veterinarian support and advice is sought early, you can help your cat have a good quality of life.

The role of your cat's kidneys

The kidneys act as a filtering system removing toxins and waste from blood. Nephrons within the kidney are the actual filtering units. The filtered waste and toxins are then sent to the bladder to leave the body in the form of urine. Everything that remains returns to the bloodstream.

Grey British Shorthair Cat

How does kidney disease affect cats?

Did you know, 30% of cats over 15 years of age have chronic kidney disease?1 Chronic kidney disease occurs when the filtering function isn't working correctly. An impaired kidney will result in more water and important compounds being removed from the bloodstream, while waste can begin to accumulate in the bloodstream.

Illustration of a vet talking to a pet owner

Identifying Chronic Kidney Disease

The signs of CKD are very difficult to spot without a medical assessment and diagnostics. Normally, the clinical signs of CKD in cats do not appear until 75% of kidney function has been lost.2 

This is where newer advances such as RenalTech(TM) by Antech Diagnostics come in. Available at select veterinarians, RenalTech(TM) can identify whether a cat will develop CKD within the next two years. With a greater than 95% accuracy as a predictive tool, RenalTech(TM) can help remove uncertainty when it comes to identifying cats with early CKD.3

If you have any concerns about your cat or would like to know more about RenalTech(TM), speak to your veterinarian.

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Signs of kidney disease in cats

The common signs of kidney disease in cats are usually difficult to spot during the early stages. However, the signs will become more noticeable as the disease progresses. If you spot any of the following signs or any unusual behavior from your cat, make sure you speak to your veterinarian so they can carry out a full examination.


Loss of body water can lead to dehydration

Increased urination - You may notice your cat is using their litter box more frequently. This could be because they are losing more water than they should during the kidneys' filtering process.

Drinking more than usual - If your cat is urinating more often, they will try to drink more to keep up with their urinary losses.


Increased levels of waste can cause a loss of appetite

Decrease in appetite - Excess waste in their bloodstream may result in your cat feeling nauseous. As a result, they may end up eating less food due to a decrease in appetite.

Weight loss - If your cat is eating less food due to a decrease in appetite, this may subsequently result in weight loss.

Lethargy - With a reduced appetite, your cat may not be eating sufficient calories or nutrients which can lead to a noticeable decrease in energy levels.

Once the amount of waste in your cat's bloodstream has significantly increased due to improper filtering in the kidneys, it is likely to have a detrimental effect on their other organs, such as the stomach.

Cat with green eyes

Can you spot the common signs?

Knowing when to take your cat to a veterinarian is important. If a veterinarian can diagnose chronic kidney disease early, this will help ensure your cat receives treatment as soon as possible.

Nutritional adjustments veterinarians may recommend

Your veterinarian may suggest a change in diet as one treatment option. If this is the case, they may also recommend ongoing alterations to their diet as the disease progresses. Renal diets are often recommended for cats that have been diagnosed with kidney disease. 'Renal' is a medical term for the kidneys and is often used when describing diets. Renal diets will contain nutrients that are likely to be increased or decreased depending on the stage of disease and specific nutritional requirements.

Here are some of the key nutrients your veterinarian may consider when recommending a renal diet:

Illustration of phosphorus


In some cases, a significant phosphorus restriction is recommended in Stage 2 by IRIS.4

Illustration of protein


Veterinarians may recommend protein restriction at early stages of CKD to help reduce nitrogenous waste products which contribute to clinical signs of renal disease.5

Illustration of antioxidants


Some studies have shown antioxidants to be beneficial in supporting kidney function.6

Cat with orange bowl

How could your cat's diet change?

Although your veterinarian will recommend a suitable diet for your cat, it's worthwhile having a deeper understanding of why your cat's diet needs to change as the disease progresses.

Illustration of cat with a Royal Canin red bowl

Benefits of a renal diet for cats

Although chronic kidney disease is irreversible, it can be managed in conjunction with your veterinarian. A change in diet is the starting point for appropriate management.

Renal diets will vary depending on the stage of chronic kidney disease that your cat has been diagnosed with and may also change as the disease progresses.

When a cat has been diagnosed with chronic kidney disease they may be suffering from nausea and other issues that can result in a lack of appetite. As a result, most renal diets are made with varying textures and aromas to encourage eating at mealtimes.

A renal diet may be recommended to help support your cat's kidney function and health.

Feed your cat Royal Canin Renal Support

If your cat has been diagnosed with chronic kidney disease or it's been predicted they will develop the disease, ask your veterinarian if a Royal Canin Renal Support diet is suitable to help satisfy their health needs.

Renal Support Early Consult

Formulated with a precise balance of nutrients, Renal Support Early Consult can help support kidneys during the early stages of CKD. Royal Canin Renal Support Early Consult also helps support digestive health and early signs of aging with highly digestible proteins, balanced fibers and antioxidants.

Royal Canin packshot of cat renal products

Renal Support diets

Available exclusively through veterinarians, dry and wet Renal Support diets are tailored to promote healthy kidney function in cats, with antioxidants, fatty acids from fish oil, restricted phosphorus, and targeted protein levels.  

Both the wet formula and dry kibble are energy-dense to help reduce the amount of food your cat needs to eat. With six options to choose from, varying in aroma, texture, size, and shape, you can mix and match all Royal Canin Renal Support diets to suit your cat's palate to encourage them to eat during mealtimes. Ask your veterinarian if a Royal Canin Renal Support diet is suitable for your cat.