Feline Kidney Disease: Yes, There's Hope!

Feline kidney disease is something every cat owner will experience if their cat lives long enough without succumbing from another disease. Most cats do not show an obvious decline in kidney function until they are well into their teens. Some less fortunate kitties have problems with kidney function, even feline kidney failure, much earlier in life.

Watch the following video to see just how long a cat can live in spite of having kidney problems. You'll be amazed.

As you can see from the above video, a diagnosis of feline kidney disease doesn’t have to mean disaster. If you find out your cat has declining kidneys, there are many actions you can take to extend his life. These treatments range from a simple change in diet or giving medication to learning to give fluids under the skin at home to the real extreme, a feline kidney transplant.

Here's How YOU Can Directly Ask Your Questions!



Feline Kidney Transplants

Granted, very few cat owners opt to have their cat go through the process of receiving a new kidney. However, some do. I will never forget the first feline kidney transplant the University of Pennsylvania School of Medicine performed. It had special meaning for me because their first recipient was one of my own patients from my cat hospital.

I had managed the cat’s kidney disease for quite some time before he went for surgery. It was important for him to become more stable before the transplant. I am happy to say the surgery was a success. The kitty lived many more years and developed other diseases, including feline hyperthyroidism and cat diabetes, which his loving parents continued to treat and the cat lived to a ripe old age.

Much more common is medical management through dietary changes, medication and administration of fluids at home. Periodic blood work is necessary to monitor the need to adjust dosages and add or discontinue medications and adjust fluid therapy.

I personally have had many of my own cats develop kidney disease and in all cases, they lived several years after the initial diagnosis. You can do as much for your own cat as I did for mine. You don’t have to be a veterinarian to care for a feline kidney disease patient at home.

Symptoms of Feline Kidney Disease

If your cat develops kidney disease, the first symptoms you will probably see are increased thirst and increased urination. Any time you observe this in your cat, regardless of age, it’s time for a trip to the veterinarian where your cat will HAVE to have blood work and a urinalysis. There are a few different cat diseases that cause an increase in thirst and urination; only an analysis of your cat’s blood will let your veterinarian know which disease is causing your kitty’s symptoms.

Other Symptoms (but don’t wait until you see these!)

• Nausea – licking lips

• Vomiting

• Constipation

• Loss of appetite

• Weight loss

• Dull, unkempt hair coat

• Bad breath (ammonia smell)

• Lethargy

• Stomach irritation

• Oral ulcers

If the condition is chronic, a cat with kidney disease can develop anemia. This can lead to

• Weakness

• Eating litter

High Blood Pressure in Cat Kidney Disease

Without getting too technical, I need to advise you that the kidneys play a very important role in blood pressure. Therefore, many cats with kidney disease develop high blood pressure.

Unfortunately, high blood pressure in cats is similar to high blood pressure in people and is a silent enemy. Over my many years of practice, I have seen all too often that the first sign of high blood pressure observed by cat owners is blindness in their cats. This is another reason to make sure your cat has regular veterinary visits even if he looks healthy to you. If early changes in kidney function are detected and blood pressure is measured, blindness can be avoided.

Laboratory Changes in Cat Kidney Disease

It is important to note that the first laboratory indication of feline kidney disease onset will be a decrease in the specific gravity of the urine. In other words, your cat’s urine will be “thinner”, more like water. This occurs before there are changes in the blood. Often, however, by the time you notice the signs of increased thirst and urination and take your cat to the vet, this early stage will have progressed to one in which there are changes in the blood.

If the feline kidney disease is not too advanced, the only blood abnormalities will be an increase in creatinine and an increase in BUN. If the elevations are slight and all other tests are normal, that is good news and may only require monitoring or a dietary change. However, further diagnostics are recommended even at this stage in order to look for possible underlying causes of the change in kidney function in the hopes of halting the underlying cause.

Additional Diagnostics

These diagnostics can include a complete urinalysis including a culture of the urine, radiographs of the kidneys (x-rays), ultrasound of the kidneys, and blood pressure measurement. Your veterinarian may also recommend a needle biopsy of the kidneys which can often be done with no or mild sedation. These tests are necessary to be able to distinguish between such things as feline kidney infection (pyelonephritis), kidney stones, cancer of the kidneys, feline polycystic kidney disease, FIP (feline infectious peritonitis), feline amyloidosis (deposits of a protein called amyloid in the kidneys), glomerulonephritis (an inflammatory disease), hydronephrosis (caused by an obstruction to the normal flow of urine), chronic interstitial nephritis, and a few other rare genetic disorders.

Chronic interstitial nephritis is the most commonly diagnosed condition; the kidneys are small and normal kidney tissue has become scar tissue. However, this may be the most common of the feline kidney diseases simply because all the other diseases, if untreated, lead to this condition. It is, therefore, very important to diagnose feline kidney disease as early as possible and look for underlying causes that may be treatable before the condition becomes chronic and irreversible or unmanageable.

A proper diagnosis is important, as always, so that the appropriate treatment can be prescribed. If there is inflammation, anti-inflammatories may be indicated whereas if there is infection, anti-inflammatories can be harmful and instead, antibiotics are needed. If there is cancer, removal of one kidney may be an option or chemotherapy. If hydronephrosis is occurring due to an obstruction from a stone or other problem, then it may be possible to remove or alter the obstruction. You can see how knowing what condition needs to be treated is so important for determining the treatment.

Chronic Feline Kidney Disease

If none of the above causes are found and if your cat has a diagnosis of chronic renal disease, then this is likely to be progressive and eventually can become very debilitating. HOWEVER, it can take a long time and many things can be done to prolong your time with your cat and keep your cat happy and comfortable.


Whether a low protein diet helps chronic kidney disease in cats or not has always been and still is a controversial topic in veterinary medicine. Some say it helps; others say it doesn’t. My experience has been that it does. When my own cats have had declining kidneys, I have always changed their diet to one lower in protein.

There are several different prescription diets available from your veterinarian that are described as being feline kidney diets. DO NOT feed your cat one of these diets in the dry form. In fact, do not feed your cat dry food period. Dry food has very little moisture in it. Canned food has much more and every cat with kidney disease needs to consume more water. Eating dry food over the course of a cat’s lifetime may indeed be one of the causative factors in the development of chronic kidney disease in so many cats.

Some of the prescription diets also restrict the protein level far too much, as you can read more about on catinfo.org The most important dietary change you can make for your cat with feline kidney disease is to switch to an all canned food diet if you have not already done so. And, to help encourage drinking, I strongly recommend the use of a cat water fountain, especially the ones seen here, since increasing moisture intake is so critical to kidney health.

Additional Treatment for Feline Kidney Disease

Other treatments for kidney disease in cats depend on the stage of the disease and the symptoms or blood abnormalities that exist. These can include:

- Anti-nausea medications

- Medications to alleviate ulcers and gastritis

- Medications to decrease elevated phosphorus which is a common problem in kidney disease

- Blood pressure medication

- Vitamins with iron for anemia

- Epogen, a replacement hormone that stimulates red blood cell production

- appetite stimulants

- potassium supplements


As kidney disease progresses, fluid therapy can become very essential. During times of crisis, the fluids may need to be administered intravenously in the hospital.

On a more chronic basis, cat owners are often taught to give fluids subcutaneously at home. This is a simple procedure that most cats tolerate very well and can extend life by months to years.

Keep in mind that this procedure is not painful for your cat, is not for the purpose of extending the life of a cat that is in pain, and is not difficult to learn to do.

While the administration of SQ fluids at home can be life-saving, I encourage you to understand that this is not an extreme, life support type of treatment, which is the impression some people seem to have until they understand it fully.


I was just told that my 13-year-old cat has early feline kidney disease. Bailey's BUN was 45. What would you recommend for this problem?

I have been feeding her Iams Prohealth Formula. I have a problem with a family member giving pounce treats and I have now asked him to stop. Will I be able to continue the Iams Prohealth or do I need to change her diet?

I have 7 kids ranging from 2 to 13 and we free feed. I want her to live healthy, but I do not have the ability to stop the free feeding due to the other cats in the house. HELP!



Hi, Rachel,

First, I want to point out that a BUN of 45 is barely elevated. Also, BUN can be elevated from things other than kidney failure. In addition, the most sensitive indicator of kidney function is not BUN, but creatinine. Did the vet tell you if the creatinine was elevated? Also, did they analyze her urine? The earliest sign of feline kidney disease is a decrease in the specific gravity (concentration) of the urine. That will occur before creatinine and/or BUN becomes elevated.

If these tests were not performed, they should be.

The value of feeding a low protein diet, such as Hill's prescription diet K/D, is somewhat controversial. Most vets, including myself, feel that a low protein diet is indeed beneficial. I have been treating cats with kidney disease for 20 years and my experience has been that those on a low protein diet feel better and live longer than those not eating a low protein diet.

K/D is not the only prescription low protein diet. Iams also has one as does Purina and other companies.

It is very difficult to feed one cat differently than the others when you have a multi-cat household. I have been in that situation myself as have many of my clients.

I have at times fed all my cats the low protein diet if one needed it and the others were not kittens or pregnant or nursing cats. You could also leave dry low protein food down all the time and supplement all except the kitty with feline kidney disease with regular canned food. At that same time, you can give the one with kidney disease low protein canned.

Other cat owners have gone to an all canned food diet so the kidney disease kitty can be fed low protein while the others eat regular, eliminating dry food altogether. This has the added benefit of offering more water due to the high water content of canned food. Increased water intake is beneficial to the urinary tract.

Others, including myself, have postponed any diet change when the kidney insufficiency is in such early stages. You are probably beginning to see there is no one right or wrong answer. It is still not completely known if feeding a low protein diet is helpful at all or if feeding a moderate protein diet is superior to a low protein one.

The most important consideration about diet for a cat with chronic feline kidney disease and any cat, for that matter, is to feed canned food only. Dry food is so deficient in water and is too high in carbohydrates for any cat and will be particularly damaging for a cat with kidney disease.

Discuss these issues with your vet, make sure all the tests have been run that I mentioned, provide fresh water at all times, and take your kitty for frequent rechecks. As kidney function changes over time, certain medications may be added that are very useful as well as other dietary changes or supplements and possibly fluid supplementation at home.

Best of luck with everything. Thank you for raising this very important question.

Best, Dr. Neely


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