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How to care for a cat with kidney failure
Consider a prescription diet.
If your cat has kidney failure, talk to your veterinarian. He or she may prescribe a special renal diet that contains restricted amounts of high-quality protein and minimal amounts of phosphate and certain minerals.
Protein, phosphate, and minerals are very difficult for the kidney to filter, so prescription diets that restrict these substances place less strain on the organ. Studies show that phosphate can also cause scar tissue to build up on the kidney, so it is doubly important to restrict phosphate in your cat's diet.