Blocked Bladder in cats


  • Having a blocked bladder (being unable to pee) is an emergency and can cause death if left untreated.
  • Contact your vet for an emergency appointment if your cat is struggling to pee.
  • A blocked bladder is often caused by an underlying problem such as stress, inflammation, infection or bladder stones.
  • Your cat will need admitting into the veterinary hospital for treatment.
  • Lifelong care will be necessary to reduce the chance of another blockage.
  • Blocked bladders are most common in male, neutered, overweight, stressed cats, and cats that eat a dry diet.

When to contact your vet

Contact your vet immediately for an emergency appointment if your cat is having difficulty passing urine. Never wait to see if your cat improves – left untreated a blocked bladder can cause death.

You know your cat – if you’re concerned it’s always best to contact your vet.

What is a blocked bladder?

A blocked bladder means that your cat can’t pee This leads to urine building up inside the bladder until it reaches bursting point. A blocked bladder is extremely serious and left untreated it can cause kidney damage, heart problems and may even burst – causing peritonitis and death.

A blocked bladder can be caused by:

Female cats very rarely develop blocked bladders. Male cats are much more likely to develop the condition because their urethra (the tube that drains urine from the bladder) is much longer, narrower and prone to blockage. Blockages are most common in overweight cats, indoor cats, neutered cats, stressed cats and cats that eat dry food.

illustration of bladder blockage in cats

A blocked bladder stops your cat from peeing


You may notice your cat struggling to pee, or showing signs of a urine infection before they develop a blocked bladder – urgent treatment is required if you notice these symptoms.

A blocked bladder may cause the following symptoms:


If your cat has a blocked bladder, they will need intensive care in a veterinary hospital until they’re out of danger and their bladder is working again – this will take a few days.

Your cat will need their bladder unblocked (under anaesthetic), a fluid drip and some investigations to find out what has caused the problem.

It’s possible to unblock most bladders by putting a thin tube into the penis and allowing the urine to drain out. Your vet will then use a variety of drugs and fluids to treat any infection, crystals, spasm or pain.

Some cats require surgery – for instance if a large stone is blocking the tube and needs removing, or if the urethra (tube that drains urine from the bladder) is too narrow. Sadly, there are some blockages that aren’t easy to treat, such as large tumours.

Photo of cat having their bladder drained by a vet

This cat is under anaesthetic having his bladder unblocked and drained

Care after a blockage

After your cat has blocked once, there is a chance they will block again. To prevent this happening, you will need to follow your vet’s advice and make some changes to your cat’s lifestyle and diet. These changes may include:

It’s very important to keep an eye on your cat’s toileting habits if they have suffered a blocked bladder in the past.

Your vet may ask you to collect a urine sample from your cat and bring it to check up appointments. Watch our video below on collecting a urine sample from your cat.

How to collect a urine sample


Despite being a serious condition, the outlook for many cats with a blocked bladder is good if they receive treatment quickly and measures are taken to stop them blocking again. A cat that doesn’t receive treatment in time is likely to die from a blocked bladder.


Treatment for a cat with a blocked bladder can become very expensive, especially if they are prone to the condition. Consider insuring your cat as soon as you get them, before any signs of illness start. This will ensure you have all the support you need to care for them.

It’s also very important to speak openly to your vet about your finances, the cost of treatment, as well as what you think is right for your cat. There are often several treatment options so if one doesn’t work for you and your cat, then your vet may be able to offer another.

Published: June 2019

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Written by vets and vet nurses. This advice is for UK pets only. Illustrations by Samantha Elmhurst.