Renal failure or kidney failure is a common problem among ageing cats. Damage to the kidneys is irreversible and they deteriorate over time. Fortunately, affected felines are still able to live a good life with appropriate treatment and diet.

A cat’s kidneys perform the following functions

  • Regulating fluid levels, maintaining water and salt balance in the body
  • Filtering and disposing of waste products in the body through urination
  • Concentrating the urine by restoring water to the body, preventing dehydration
  • Maintaining the balance of electrolytes (salts in the body’s cells which are necessary for survival) in the body
  • Producing erythropoietin which stimulates red blood cell production
  • Producing renin which controls blood pressure

Chronic Renal Failure (CRF)

This is a progressive and irreparable deterioration of the feline’s kidney. Affected cats are unable to filter, process and eliminate waste products effectively, resulting in a build up of toxins in the blood stream, which makes the cat sick. The common causes are age, genetics, environment and diseases.

Acute Renal Failure (ARF)

ARF is an abrupt shutdown of kidney functions, often triggered by poisoning, trauma, infection, or urinary obstruction. It can quickly become fatal and immediate veterinary treatment is crucial. With early treatment, some cats can be saved and normal kidney function may be restored. However, others may be left with residual kidney damage.

Signs and Symptoms of Kidney Failure

Most cats do not exhibit signs of CRF until approximately 70 percent of the kidney is damaged because normal functioning of the kidney requires only 30 percent. Symptoms vary among individual cats but the common ones include:

  • Increased thirst (polydipsia)
  • Excessive urination (polyuria)
  • Loss of appetite
  • Nausea and vomiting
  • Weight loss
  • Poor hair coat
  • Emaciation


Your vet will perform a thorough physical check on the cat, taking into account its background history of symptoms and any possible incidents that might have caused this condition.


The main purpose of treatment is to slow the progression of CRF and provide a better quality of life. Loss of appetite may ensue and without food, cats can develop a potentially fatal liver disease called hepathic lipidosis. There are many possibilities for poor appetite including acid in the stomach, dehydration or anaemia. Foods with high phosphorus levels can hasten the progression of the disease. Vets may recommend prescription foods intended to help cats cope with CRF. They are relatively low in phosphorus, but high in quality protein and sodium to protect the kidneys from further damage. Felines generally ingest water from their food, thus canned food is recommended as it contains more fluid than kibble. Ensure that a fresh supply of water is available at all times.

Fluid Therapy

Without sufficient hydration, blood flow through the kidneys is reduced, causing the kidney to deteriorate further. If the cat is suffering from severe dehydration, intravenous fluid therapy may be needed. Alternatively, regular subcutaneous fluids—a method of hydrating the cat by introducing fluids under the skin prevents frequent vomiting that leads to dehydration—can also help. However, this procedure is not suitable for cats with pre-existing heart conditions.


A variety of medications is available to alleviate side effects and symptoms. Cats experiencing frequent vomiting are prescribed antacids, which help to reduce the symptoms of uraemic gastritis (inflammation of stomach due to retention of waste products and hormones that the kidneys normally excrete). As the disease progresses, renal failure lessens the production of erythropoietin causing affected cats to be anaemic. 


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