Reduced Kidney Function in Cats

We're growing old together.
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You love that old cat. That's why a diagnosis of kidney disease is so scary. Don't despair — proper care and feeding can keep Kitty around for a while. Kitty might have lost up to 75 percent of his kidney function before you even notice signs of the disease.

Kidney Disease

Did you ever wonder what your cat's kidneys do, exactly? Kitty's two kidneys filter waste products from his body, control his blood pressure, produce urine, create erythropoietin -- necessary for red blood cell production -- and regulate sodium, phosphorous, calcium and potassium. They're very important organs. As Kitty's kidneys become less functional, toxins aren't excreted as efficiently and, as time goes on, begin building up in his body.


Because the early signs of kidney disease are subtle, keep a close eye on your older cat and watch for even minor changes in his drinking, eating and peeing habits. During his annual vet check-up, your vet should perform a urinalysis and take blood work to test Kitty's kidney levels. Obvious symptoms of kidney disease don't show up until Kitty's kidneys are operating at 25 percent capacity, according to the Merck Veterinary Manual. At that point, Kitty might start drinking and peeing excessively. Other symptoms include weight loss, lack of appetite, vomiting, bad breath, mouth ulcers, depression and poor coat quality. Because the kidneys regulate blood pressure, very high pressure can cause retinal damage, leaving Kitty blind.


To diagnose chronic kidney disease, your vet takes a urine sample from Kitty and tests it for changes, along with blood work. She tests his blood for blood urea nitrogen and creatinine levels to determine if his kidneys are failing. Once she's confirmed the diagnosis, your vet might flush out his kidneys through the use of intravenous fluids containing electrolytes. Kitty's kidneys might start functioning better temporarily after this procedure. Depending on the cat, it could last a short time or for years.


There is no actual cure for chronic renal failure in cats, with one extremely expensive exception. Standard treatment involves dietary adjustments and giving Kitty subcutaneous fluids, if necessary. Your vet will recommend a special diet that doesn't stress Kitty's kidneys. She may also suggest supplements, such as taurine or certain vitamins. If Kitty has high blood pressure, she might prescribe medication to control it, along with other drugs that might help Kitty.


There is one potential cure for kidney failure -- a kidney transplant. That's if you have the means to pay for a kidney transplant and your vet thinks Kitty could benefit from this surgery. This operation is done at relatively few veterinary hospitals. Because a donor cat is needed, you'd have to agree to adopt this cat and give him a home.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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