Acute kidney failure in cats

Acute kidney (renal) failure is a life-threatening illness. Cats of any age, breed, or sex can be affected. Acute kidney failure usually develops within a matter of days and symptoms become very serious very quickly.

Acute kidney failure (injury) happens when the kidneys suffer damage and stop working. This leads to a build-up of fluid and toxic waste inside the body. Acute kidney failure can sometimes be reversed with rapid and intensive vet care. But it’s a life-threatening illness and around 50% of cats who develop acute kidney failure won’t survive. Cats who do recover may develop long-term health problems, especially chronic kidney disease (CKD). The sooner acute kidney failure is recognised and treated, the better the chances of long-term recovery.


What is acute kidney failure in cats?

The kidneys are two essential organs in your cat’s abdomen. Their functions include:

  • Controlling fluid and salt levels in the body
  • Removing toxins and waste from the blood
  • Producing some hormones.

When the kidneys stop working, the body can’t control fluid and salt levels. All the organs and tissues which depend on this control also stop working. This includes the heart, muscles and brain. The damage gets worse as harmful waste products continue to accumulate.

Acute kidney disease in cats


Causes of Acute Kidney Failure



  • Chemicals- antifreeze, cleaning products, batteries, insecticides, paint
  • Plants- lilies, bulbs
  • Some Foods- raisins, chocolate
  • Anti-parasite treatments
  • Certain medicines – some painkillers, antibiotics and antifungal drugs



  • Viral infections (FIP, FeLV, FIV)
  • Severe or recurrent kidney infections (pyelonephritis)
  • Parasite infections- toxoplasmosis


Reduced blood flow

It deprives the kidneys of vital oxygen from red blood cells

  • Trauma (road accidents)
  • Shock (sepsis, organ failure)
  • Heart failure (cardiomyopathy, cardiac failure)
  • Severe dehydration


Back pressure

Damage to kidney tissue when urine can’t flow from the kidneys to the bladder and out of the body

  • Blocked bladder.
  • Crystals or stones blocking the kidneys or the ureters

Acute kidney disease in cats

Kidneys produce urine, which passes to the bladder through small tubes called ureters. Urine leaves the bladder (and the body) through another wider tube, called the urethra. If urine can’t escape out of the bladder, fluid builds up inside the kidneys, making them swell. This causes buildup of pressure inside the kidneys. If not treated early, the resulting damage to kidney structure can lead to kidney failure.



It may begin in the kidneys themselves or spread there from other parts of the body.


Symptoms of acute kidney failure in cats

Symptoms of acute kidney failure in cats will often overlap those of other serious illnesses.

  • Not eating
  • Vomiting and diarrhoea, possibly with blood
  • Lethargy and weakness
  • Severe halitosis (bad breath)
  • Mouth ulcers and drooling saliva
  • Going blind suddenly
  • Collapse and seizures

Find your nearest vet if your cat is collapsed, having seizures, or has been vomiting blood.


Cats at higher risk of developing acute kidney failure

Some cats will have more risk of developing acute kidney failure, depending on their lifestyle and general health.


Outdoor cats

They are more likely to encounter antifreeze (ethylene glycol), and poisonous plants in gardens.


Older cats

Older cats are more likely to have other illnesses and age-related changes which predispose them to acute kidney failure. They may already suffer from chronic kidney disease.


Cats with other illnesses

Illnesses which affect the blood supply and health of the kidneys. For example:

  • Chronic kidney disease
  • Overactive thyroid gland (hyperthyroidism)
  • Pancreatitis
  • Heart disease
  • Cats with urinary tract disease (FLUTD), especially overweight indoor male cats
  • Kidney and bladder stones (urolithiasis)


Certain breeds

Breeds can have inherited problems that weaken their kidneys. This makes them prone to chronic kidney disease and then acute kidney disease. This is known as acute-on-chronic kidney disease.

  • Persian-  (polycystic kidney disease, PKD)
  • Siamese and Abyssinian- (renal amyloidosis)

Cats receiving certain medication. All medicines can have side effects. Some can damage your cat’s kidneys. This may happen even without taking more than the recommended dose

  • Painkillers (non-steroidal anti-inflammatory drugs)
  • Certain antibiotics
  • Antifungal treatments


Is my family at risk of catching acute kidney failure?

Acute kidney failure is not in itself a risk to humans or to other pets.

Viruses which cause kidney disease may spread between cats who live together. For example:

  • FIP (Feline Infectious Peritonitis)
  • Felv (Feline Leukaemia Virus)
  • Fiv (Feline Immunodeficiency Virus)



Diagnosis of acute kidney failure in cats

Vets diagnose acute kidney failure from the following checks and tests:

  • Symptoms
  • History
  • Blood tests to check for levels of important proteins, chemicals and electrolytes (salts) in the blood
  • Urine test – analysis and bacterial culture
  • Blood pressure check
  • Ultrasound Scan
  • X-rays

Vet treatment

Vet treatment for acute kidney failure

Acute kidney failure is a life-threatening condition that needs intensive care at a vet clinic or hospital.


Intensive vet care

  • Fluids directly into your cat’s veins to flush the kidneys
  • Pain relief and Antibiotics to control infection
  • Rebalancing electrolytes (salts) in the body
  • Protecting stomach and intestines from acid and toxin damage (gastrointestinal protectants)
  • Controlling blood pressure
  • Medicine to start the kidneys making urine again
  • Treating the underlying cause of the kidney failure if possible
  • Replacing essential vitamins


Specialist treatments

  • Kidney dialysis – aims to keep cats with acute kidney failure stable while the kidneys recover. It’s a specialist treatment carried out in special veterinary hospitals. It’s only appropriate if the underlying cause has been found and is curable.
  • Kidney transplants?  Kidney transplants for cats happen in some countries. There are welfare and ethical concerns for both the donor cat and the sick cat. Kidney Transplants are banned in the UK. A kidney transplant wouldn’t help a cat with acute kidney failure. The disease develops suddenly and there’s widespread damage to other organs.

Home treatment

How to look after a cat with acute kidney disease at home

There are no home remedies. Acute kidney failure needs intensive treatment at a vet clinic.

Cats who recover need ongoing care at home and regular check-ups with a vet.

  • Keep your cat indoors during recovery
  • Give prescribed medicines at the right time and dose
  • Encourage your cat to drink lots – provide a water fountain and add water to food
  • Feed your cat a special prescription diet recommended for kidney disease
  • Encourage your cat to eat – warm up food or add in salt-free stock
  • Give recommended vitamin supplements


Living with a cat with acute kidney failure

Cats who survive the early stages of acute kidney failure need ongoing treatment at home. They may develop long-term complications, including chronic kidney disease and high blood pressure.

For the best possible outcomes:

  • Encourage your cat to drink lots and provide lots of opportunities
  • Feed your cat a prescription kidney diet
  • Give vitamin supplements recommended for cats with kidney disease
  • Keep up to date with preventive care, including vaccinations, flea treatment and worming
  • Remove house plants and flowers which may cause further harm


Quality of Life

For those who do survive the acute illness, there is often a long road to recovery. Your cat may not fully recover or may seem to do well for a while at home, then suffer recurring illness. When this happens, you may worry about your companion’s quality of life. You wonder if it’s fair to carry on with treatment, or whether the time’s come to think about euthanasia.


When to say goodbye

You may be anxious about how you’ll know if it’s time to say goodbye. It’s a decision that’s very hard to make and distressing for everyone involved. The best any of us can do is focus on what’s best for our beloved companion. We can start by thinking about their quality of life.

  • Do good things outweigh the bad?
  • Is your cat still interested and responsive?
  • Is pain or distress controlled?
  • Is giving medication straightforward or is it a fight that’s worsening quality of life for both you and your cat?
  • There are guides available online to help you assess your cat’s quality of life

Talk things through with a vet if you are concerned about your cat’s quality of life.


Tips for preventing acute kidney failure in cats

  • Ensure your cat has access to lots of clean water
  • Keep poisons out of sight and reach of cats, including household chemicals, certain houseplants and flowers and human foods.
  • Only use medicine approved for cats and advised by a vet. Human and dog medicines can be very dangerous for cats
  • Ensure your cat has a good quality diet suitable for their age and lifestyle
  • Feed a wet diet if your indoor cat does not drink much
  • Keep your cat slim and as active as possible, especially indoor cats. Overweight male cats who live indoors are at the greatest risk of urinary tract blockages
  • Ensure your cat is up-to-date with regular vaccinations, worming and flea control.
  • Treat other illnesses promptly

When to worry

When to worry about acute kidney failure in your cat

Sadly, half of the cats who get acute kidney failure don’t recover. Some die before the condition is recognised and treated. Others succumb in the early stages of treatment, despite the best efforts of their owners and vets.


Call your nearest vet practice if your cat:

  • Stops producing urine
  • Collapses
  • Stops drinking
  • Seems suddenly blind
  • Has a seizure

Joii can help with:

  • Finding a kidney diet your cat will eat
  • Giving medicine to your cat
  • Recognising household risks
  • Talking through end of life care
  • Bereavement support


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