Kidney Disease in Cats

Kidney disease is common in older cats and can be easy to miss because cats often hide illness well. Early detection and ongoing veterinary care can make a meaningful difference in comfort, hydration, and quality of life.

Urgent

Kidney disease needs prompt veterinary attention

Chronic kidney disease usually develops over time, but cats may look normal until significant kidney function has already been lost. Schedule a veterinary visit promptly if your cat is drinking or urinating more, losing weight, vomiting, seeming dehydrated, or acting less social. Seek emergency care right away for collapse, severe lethargy, repeated vomiting, inability to keep water down, seizures, blindness, or trouble urinating.

Symptoms to Watch For

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Drinking more

Many cats with kidney disease start drinking noticeably more water.

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Urinating more

Larger clumps in the litter box can be an early clue.

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Weight loss

Weight loss and muscle loss may happen gradually and be mistaken for aging.

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Poor appetite

Cats may eat less, become picky, or stop eating when nausea worsens.

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Vomiting or nausea

Nausea, drooling, lip-smacking, or vomiting can occur as waste products build up.

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Poor coat and low energy

A dull coat, hiding, weakness, or less grooming can signal illness.

What Causes Kidney Disease

In cats, kidney disease is often chronic, meaning damage builds slowly over months to years. Sometimes the exact original cause is never identified. Chronic kidney disease can develop after congenital kidney problems, kidney infections, inflammation of the kidney filters, kidney stones or ureteral stones, tumors, amyloidosis, or some viral diseases. Acute kidney injury can also happen suddenly from toxins, severe dehydration, reduced blood flow, or urinary blockage, and some cats may be left with lasting kidney damage afterward. Certain inherited problems are relevant in cats, especially polycystic kidney disease in Persian cats and related breeds.

  • Older age is a major risk factor; chronic kidney disease is especially common in senior cats.
  • Inherited polycystic kidney disease is seen most often in Persian cats and related breeds such as Himalayans, Exotic Shorthairs, British Shorthairs, Scottish Folds, Chartreux, Burmillas, and Siberian Neva Masquerades.
  • Other possible contributors include chronic infections, kidney inflammation, stones, hypertension, and protein loss in the urine.
  • Because cats hide illness well, subtle changes at home may be the first sign something is wrong.
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How It's Diagnosed

Your veterinarian will usually combine history, a physical exam, blood work, and urine testing to diagnose kidney disease and determine how advanced it is. Testing often includes kidney values such as creatinine and SDMA, urinalysis to assess urine concentration, and checks for protein in the urine. Blood pressure measurement is important because hypertension commonly occurs with feline kidney disease and can damage the eyes, brain, heart, and kidneys. Imaging such as ultrasound or X-rays may be recommended to look for stones, cysts, cancer, or structural changes. Many veterinarians stage chronic kidney disease using IRIS guidelines and then further classify it by proteinuria and blood pressure to guide treatment and monitoring.

  • Common tests: chemistry panel, CBC, urinalysis, urine protein testing, and blood pressure.
  • SDMA may help identify reduced kidney function earlier than creatinine in some cats.
  • Ultrasound can be especially useful if your vet suspects stones, polycystic kidney disease, obstruction, or cancer.
  • Follow-up testing is usually needed because treatment is based on stage, hydration, appetite, blood pressure, phosphorus, and other complications.
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Treatment Options

Treatment depends on whether the problem is acute or chronic, how advanced it is, and whether complications are present. For many cats with chronic kidney disease, the foundation of care includes a prescription kidney diet, maintaining hydration, and regular monitoring. Your veterinarian may also recommend medications or supportive care to manage nausea, vomiting, poor appetite, phosphorus imbalance, low potassium, hypertension, anemia, proteinuria, or dehydration. Some cats benefit from fluid therapy, but the plan should be individualized by a veterinarian. If there is an underlying cause such as infection, stones, obstruction, or polycystic kidney disease, treatment may also target that condition.

  • Therapeutic kidney diets are commonly recommended and can be an important part of long-term management.
  • Fresh water access, good hydration, and recheck visits are key parts of home care.
  • Treatment often focuses on quality of life: appetite, nausea control, hydration, blood pressure, and comfort.
  • Call your vet promptly if your cat stops eating, vomits repeatedly, seems very weak, or suddenly worsens.
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30–40%
Estimated proportion of cats over 10 years affected by chronic kidney disease
81%
Estimated proportion of cats over 15 years affected by chronic kidney disease
7+ years
Typical age range when chronic kidney disease becomes much more common
1 in 3
Approximate incidence reported in Persian cats for inherited polycystic kidney disease

Living with Kidney Disease

Before
After
Waiting for obvious illness
Track water intake, appetite, weight, litter box output, and behavior so subtle changes are caught earlier.
Feeding any diet your cat will eat
Work with your vet on a kidney-supportive nutrition plan and transition foods carefully if recommended.
Assuming vomiting or weight loss is just aging
Treat these changes as reasons to call your vet, since cats often hide chronic illness.
Irregular monitoring
Keep scheduled rechecks for blood work, urine testing, blood pressure, and treatment adjustments.

Frequently Asked Questions

Is kidney disease common in cats?
Yes. Chronic kidney disease is one of the most common diseases seen in older cats, especially seniors. It becomes much more common after about 7 years of age.
What are the first signs of kidney disease in cats?
Early signs are often subtle and may include drinking more, urinating more, weight loss, a poorer coat, reduced appetite, or lower energy. Because cats hide illness well, these changes can be easy to miss.
Can kidney disease in cats be cured?
Chronic kidney disease usually cannot be cured, but it can often be managed. Many cats do better with early diagnosis, prescription diet, hydration support, and treatment for complications such as nausea, high blood pressure, or abnormal phosphorus levels.
How do vets test for kidney disease?
Diagnosis usually includes blood work, urinalysis, and a physical exam. Your vet may also check SDMA, urine protein levels, blood pressure, and imaging such as ultrasound or X-rays to look for underlying causes or complications.
When should I take my cat to the vet for possible kidney disease?
Schedule a visit promptly if your cat is drinking more, urinating more, losing weight, vomiting, or eating poorly. Go to an emergency clinic right away for collapse, severe weakness, repeated vomiting, not drinking, sudden blindness, seizures, or trouble urinating.
Are some cat breeds more likely to have kidney disease?
Yes. Persian cats have the highest reported incidence of inherited polycystic kidney disease, and related breeds such as Himalayans, Exotic Shorthairs, British Shorthairs, Scottish Folds, Chartreux, Burmillas, and Siberian Neva Masquerades can also be affected.

Disclaimer: The information provided in this article is for educational purposes only and does not constitute veterinary medical advice. Reading this content does not establish a veterinarian-client-patient relationship. Every pet is different — always consult a licensed veterinarian before making decisions about your pet's health, diet, or care. If you'd like personalized guidance, you can talk to one of our vets. If your pet is experiencing a medical emergency, contact your local emergency animal hospital immediately.

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