Quick answer
Cat kidney disease is one of the most common problems in older cats, affecting up to 40% of cats over 10 and up to 80% over 15. The long-term form (CKD) can't be cured, but a kidney diet, extra fluids and treatment of problems like high blood pressure can keep many cats comfortable for years. Sudden kidney failure from a toxin such as lilies or antifreeze is an emergency.
What is cat kidney disease?
Cat kidney disease means the kidneys can no longer filter waste from the blood and balance water and minerals as well as they should. Vets split it into two kinds.
Chronic kidney disease in cats (CKD) develops slowly over months or years. It’s mostly a disease of older cats, and Cornell Feline Health Center reports it in up to 40% of cats over 10 and 80% over 15. It can’t be cured, but it can be managed.
Acute kidney injury happens over hours or days. Common causes are toxins (lilies, antifreeze, some human painkillers), a blocked bladder, infection or severe dehydration. It’s an emergency, but unlike CKD it’s sometimes reversible.
“Kidney failure in cats” usually refers to the late stage of either kind, when the kidneys can’t keep up and waste builds up in the blood.
What are the signs of kidney disease in cats?
Early CKD often has no signs at all. Cats usually lose about two-thirds of their kidney function before any signs appear, which is why yearly senior checkups with bloodwork matter.
As it progresses, you may notice:
- Drinking more and peeing bigger clumps in the litter box (see cat drinking a lot of water)
- Weight loss and muscle loss along the spine
- A picky or poor appetite, sometimes stopping eating altogether
- Vomiting, especially in the morning
- A dull, unkempt coat, bad breath and low energy
- Sudden blindness or dilated pupils, from high blood pressure damaging the eyes
| Sign | What it may mean | Urgency |
|---|---|---|
| Drinking and peeing more | Kidneys can’t concentrate urine | See vet soon |
| Slow weight loss, picky eating | Disease progressing, nausea | See vet soon |
| Sudden blindness | High blood pressure | Emergency |
| Not eating, repeated vomiting, weakness | Uremic crisis or acute injury | Emergency |
Drinking more and losing weight can also mean hyperthyroidism or diabetes, so your vet will test for those too. Not sure how fast to act? Our should I take my cat to the vet? checker can help.
How do vets diagnose CKD in cats?
Diagnosis needs bloodwork and a urine test, ideally repeated on a well-hydrated cat to confirm the results are stable.
- Creatinine and BUN: waste products that rise as kidney function falls.
- SDMA: a newer marker that often rises earlier than creatinine and isn’t affected by muscle loss.
- Urine specific gravity: shows how well the kidneys concentrate urine. Dilute urine is an early clue.
- Urine protein (UPC ratio): protein leaking into urine is linked to faster progression.
- Blood pressure: high blood pressure is common in kidney disease and damages the eyes, heart and brain.
- Ultrasound or X-rays: to look for stones, cysts or a blockage.
Your vet then assigns an IRIS stage from 1 to 4. Our guide to cat kidney disease stages explains each stage and what it means for your cat.
How is chronic kidney disease in cats treated?
Treatment aims to slow the disease and keep your cat eating, hydrated and comfortable. What your vet recommends depends on the stage and on your cat’s other health problems.
| Treatment | What it does |
|---|---|
| Prescription kidney diet | Lower phosphorus and moderate protein. The best-proven way to slow the disease |
| More water | Wet food, water fountains and extra bowls. Later, fluids under the skin given at home |
| Phosphate binder | Mixed into food when diet alone doesn’t control phosphorus |
| Blood pressure medicine | Amlodipine is commonly used to protect the eyes and kidneys |
| Protein-loss medicine | Such as telmisartan or benazepril when urine protein is high |
| Appetite and anti-nausea medicine | Helps cats keep eating, which is vital |
| Potassium or anemia treatment | For low potassium or a low red cell count in later stages |
Your vet will set the drug and the dose for your cat. Keep human medicines out of the plan entirely. Ibuprofen and aspirin reduce blood flow to the kidneys and can speed up kidney damage, and acetaminophen (paracetamol) is poisonous to cats as well.
Most cats need a recheck every 3 to 6 months, sooner after a change in treatment.
How much does it cost to treat cat kidney disease?
Costs build over time because chronic kidney disease is lifelong. These are typical ranges at a regular US clinic.
| Item | Typical cost |
|---|---|
| Senior blood and urine panel | $150 – $350 |
| Blood pressure check | $30 – $75 |
| Prescription kidney diet (per month) | $50 – $120 |
| Home fluid supplies (per month) | $30 – $80 |
| Hospital stay for a kidney crisis | $1,500 – $4,000 |
To estimate your own bills, try the cat vet cost estimator, or see what a cat vet visit costs.
How long can a cat live with kidney disease?
It depends mostly on the stage at diagnosis and how your cat responds to treatment. Cornell Feline Health Center reports that cats diagnosed in stage 2 live 2 to 3 years on average, while cats diagnosed in stage 4 average less than 6 months. Many cats found early through routine bloodwork live well for years.
Signs that kidney disease is getting worse include steady weight loss, refusing food for more than a day, and vomiting more often. Call your vet if you see these. For other long-term problems in older cats, browse our cat health problems guides.
Frequently asked questions
Is kidney disease painful for cats?
Early kidney disease usually isn't painful. In later stages, nausea, mouth ulcers and dehydration make cats feel unwell, and your vet can treat each of these to keep your cat comfortable.
Can cat kidney disease be reversed?
Chronic kidney disease can't be reversed, but its progress can often be slowed. Sudden (acute) kidney injury is different, and some cats recover much or all of their kidney function if treated early.
What should I feed a cat with kidney disease?
Most cats do best on a prescription kidney diet, which is lower in phosphorus and moderately restricted in protein. Wet food adds water. Change foods slowly, and ask your vet before switching.
Is kidney disease in cats hereditary?
Age is the main risk factor. One inherited form, polycystic kidney disease, is found mostly in Persians and related breeds, and a DNA test is available.
Sources
Written by the CatsMed Team from the sources above. This guide isn’t reviewed by a veterinarian and isn’t a substitute for one. See how we research.
