SPCA New Zealand
Advice & welfare

Kidney problems in pets

The kidneys are organs that are essential to remove waste products from the bloodstream, regulate the levels of certain nutrients such as potassium and sodium, conserve water, and produce urine and hormones like erythropoietin, which stimulates the production of red blood cells.

The kidneys have a large amount of spare capacity to perform their various functions, so at least two-thirds of the kidneys must be damaged before signs of kidney (renal) disease are easily seen. In many cases, this means that the damage to the kidneys has been going on for months or even years (chronic) before failure becomes obvious. Chronic renal failure (CRF) is mainly a problem in older cats, but can also affect dogs as they age too. Occasionally the kidneys can fail very suddenly, especially in younger animals (acute renal failure) following exposure to certain toxins (such as lilies, raisins and grapes) or severe infections.

CRF is the end stage of a number of different disease processes: it can be the result of a genetic defect like polycystic kidney disease, bacterial or viral infection, inflammation and damage to the kidneys’ filtration membrane (glomerulonephritis), cancer, kidney stones, amyloidosis (abnormal protein build-up that blocks the kidney function) and other disease processes.

Symptoms and Diagnosis

Early signs of kidney disease are generally weight loss, poor coat quality and an increase in water consumption. Initially the kidneys cope with their inability to efficiently remove waste products by excreting the wastes in a larger volume (by producing a larger amount of more dilute urine). This is known as compensated renal failure – when water consumption increases to prevent dehydration. After approximately two-thirds of the kidney tissues have failed, there is a rapid rise in waste products in the bloodstream and the kidney disease becomes more severe.

As the disease progresses, animals can develop bad breath (halitosis), decreased appetite, vomiting and lethargy, and they are sometimes anaemic because they are no longer producing enough red blood cells. In addition to the veterinarian’s findings during a clinical examination, kidney disease is diagnosed with blood tests and urine samples. Unfortunately, once the kidneys are damaged, they have a limited ability to recover. However, with careful management and treatment, further deterioration can be slowed so that your pet may have several years of active good-quality life ahead.


For patients who are sick, dehydrated and not eating, it is necessary to hospitalise them and to provide fluid support to flush out excess waste products from the bloodstream, which cause nausea, so that they feel well enough to start eating again. This is especially important in cases of acute renal failure.

Anti-nausea drugs can also be given to help control vomiting. At our veterinary practice we often integrate complementary therapies to help support kidney function. Long term, the most important management tool is to provide goodquality nutrition and maintain the animal's hydration via easy access to fresh water (and possibly the administration of subcutaneous fluids). It is important to feed a high-quality protein in the correct amounts as part of a well-balanced diet which is low in phosphates to help lower the level of waste products in the bloodstream.

Phosphate can contribute to the feeling of nausea that affects patients with renal disease, and contributes to further damage of the kidneys. There are special prescription diets that have been shown to improve the outcomes for animals with kidney disease. Phosphate binders (in the form of a powder) can be added to food to limit the body’s absorption of phosphates if a prescription diet is not able to be used. At our veterinary practice we may suggest supplementing the diet with water-soluble vitamins B and C, as they are flushed out of the body quickly by increased urination.

We advocate using a good-quality multivitamin that may help to supply optimal amounts of these micronutrients, as well as essential omega 3 fatty acids that may help to reduce inflammation and promote the oxygenation of cells. Antioxidant supplements such as co-enzyme Q10 may also be a valuable support. We also use other complementary therapies to try and help maintain a good quality of life and support kidney function. Animals with kidney disease may have high blood pressure, and for these animals it is important to give medication to reduce the blood pressure to a more normal level.

Bob's Story

For most pets with kidney disease, their quality of life can be supported and improved for many months and even years following diagnosis. It is important to work with your veterinarian to make a plan that is suited to your individual animal’s situation, and also to recheck and adjust the treatment plan as the disease progresses. Some of my most successful kidney disease patients are those that I have never met, but I have worked with their owner/guardian and local vet through a phone consultation to integrate complementary therapies. A typical example is Bob who was diagnosed with CRF by his local vet.

Being an older fellow who was easily stressed when going in the car, his owner wanted to help him with whatever she could do for him at home. Bob was lethargic, had a poor appetite and vomited often. His blood tests showed elevations of his kidney parameters, indicating that more than two-thirds of his kidneys were damaged beyond repair, and his vet was worried about his quality of life.

I recommended a well-balanced diet with high-quality protein and optimal amounts of vitamins, antioxidants and omega 3 fatty acids. In addition to this, we made Bob a combination remedy of complementary therapies, which his owner could just drop into his water bowl, since he was difficult to dose directly. All that was needed was for him to sip a few drops of the water to receive a dose, and because of his kidney disease, he was drinking a lot of water which made this easy. Bob really enjoyed his new diet and after a few days his owner reported that he was “playing like a kitten” for the first time in months. His vomiting stopped and he went on to live happily for years, much to the delight of his owner! If your pet is suffering from a kidney condition, please first seek advice from an experienced veterinarian on how to manage this condition, and if the use of complementary or alternative therapies would be effective for your pet.

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