Seeing blood in your cat’s urine is very worrisome, and it’s important to address the problem right away.

When cats have blood in their urine, also known as ‘hematuria’, it is an indication of a larger health problem that requires veterinary care.

If you take your cat to the vet right away, they can determine the cause of the problem and prescribe appropriate treatment to get your cat feeling healthy again.

What are the signs of hematuria?

It can be difficult to spot blood in your cat’s urine, but there are other signs that your cat could be struggling with hematuria. If you notice any of these signs, check their litter box for blood in their urine, and take them to the vet right away for treatment.

  • Pink or red urine
  • Increased or decreased trips to the litter box
  • Urinating outside the litter box
  • Excessive or aggressive grooming of the genitals
  • Meowing or other vocalizations while urinating
  • Change in odor of the urine

What are the causes of hematuria?

There are a few different things that can cause hematuria. Hematuria is actually fairly common in cats, but there are treatments available to help your cat heal. Here are some of the causes of hematuria.

Pandora Syndrome

Pandora syndrome is sometimes called Feline Idiopathic Cystitis (FIC). This is the most common cause of hematuria in cats. Pandora syndrome is not the same thing as a urinary tract infection, although it has similar symptoms- importantly, feline idiopathic cystitis is sterile- no bacteria are found when the urine is examined. No crystals can be found to explain the pain and bleeding either.

In fact, FIC doesn’t have a known cause, hence ‘idiopathic’, but we know a lot more about it than we used to. FIC can develop as a result of stress, obesity, hormone issues, and other environmental factors, and cats that are prone will often have recurrent bouts.

Urinary Tract Infection

A urinary tract infection (UTI) in cats is just the same as in humans. Bacteria invade the urinary tract, causing inflammation, bleeding, and pain when urinating.

Importantly, a urinary tract infection is not common in cats, and usually there’s an underlying reason why an infection is present. Diabetes, kidney disease, or other conditions affecting the immune system are things to look out for if your cat is diagnosed with a UTI.

Urinary Crystals and Stones

Urinary crystals (or ‘crystaluria’) occur when certain chemicals and compounds in the urine form crystals. Whilst these crystals are microscopic and unlikely to cause major trouble on their own, once there are lots they can cause irritation and blood in urine. They can even mass together to form a urinary stone- a hard clump of crystals that can be anywhere from a grain of sand to a fist in size.

Bladder tumor

Although fairly rare, another important cause of blood in cat’s urine is a bladder tumor. As the lump grows, small amounts of blood can be released into the urine. And, because of it’s location, it’s likely the lump will be uncomfortable, causing the same symptoms as cystitis- blood, pain, and frequent litter-tray visits.

Urethral Obstructions

Along with ‘urethral plugs’ and ‘urethral spasm’, many of these causes can potentially cause a urethral obstruction, commonly called a ‘blocked cat’. Urethral obstructions happen when something gets stuck in the urethra, preventing the flow of urine out of the body. This quickly backs up, causing severe pain and life-threatening disease. They are much more common in male cats, and any male cat that is not peeing, is visiting the tray more than often, or is licking his genitals, should be taken to the emergency vet immediately.

Urethral obstructions need to be treated immediately or they can become life-threatening, so take your cat to the vet right away.

What should I expect at the vet?

blood urine cat check up

When you arrive at the vet, they will perform a number of tests to determine the cause of the hematuria and prescribe appropriate treatment.

They will start by taking a medical history of your cat and performing a basic physical examination. Then, they may do a complex urinalysis to assess the bacteria in the urine, as well as bloodwork to get a better idea of your cat’s current health.

Depending on the results of the previous tests, they may use an x-ray or an ultrasound to determine if your cat has kidney stones or other blockages that could be causing the problem.

Treating and Preventing Hematuria

The treatment for hematuria will depend on its cause. If your cat has a urethral blockage, your vet will need to remove it using a catheter. If they are struggling with Pandora Syndrome, they will likely prescribe pain medications, and maybe even anti-spasm medications to reduce tension and inflammation. True bacterial infections will require antibiotics, and tumors can be operated on or be candidates for chemotherapy or radiation therapy.

In all cases, increasing your cat’s fluid intake is helpful- your vet might recommend that your cat is put on a drip at first to rehydrate them, but you’ll need to encourage better hydration at home.


blood cat urine hydration

There are also many things you can do to prevent hematuria in the future. The first is to make sure your cat is properly hydrated and has access to water.

You may need to get them a water fountain to encourage them to drink more, or increase their consumption of wet food, which has a higher water content. Several water bowls, scattered throughout the house, can help- especially if they’re all a bit different to provide novel interest. You can read more about encouraging cats to drink here.

Recently, there has been some research into ‘water supplements‘ for cats- nutrient-enriched water that can be added to water bowls to encourage drinking. The early results are promising, and it’s likely these will be available soon.

Weight Management

Since obesity can also cause hematuria in cats, it’s important to keep them at a healthy weight.

Make sure they are getting proper nutrition as well as enough exercise throughout the day. To encourage them to exercise, invest in some new toys or cat trees to give them more to do throughout the day.

Stress Management

Long-term, low-grade stress is thought to be the main cause of Pandora syndrome, so take steps to make sure your cat feels comfortable and relaxed in your home. This may mean getting them new bedding or separating them from other animals in the house. Your vet will be able to give lots of advice to help with stress in your cat, but sometimes using a behaviorist can give you further support.

Litter Box

blood urine cat litter box

Make sure your cat’s food and litter box are in completely separate areas. You should also make sure your cat’s litter box is big enough for them to comfortably go to the bathroom, and make sure you are cleaning it regularly. Many people don’t know that it’s recommended to have several litter trays- at least one per cat, and one spare. These should be spread throughout the house to encourage your cat to urinate when they need to rather than holding onto their urine, increasing the chance of crystals forming.

If you notice blood in your cat’s urine, take them to see the vet as soon as possible.

When untreated, this condition can become very dangerous for your cat. With quick treatment, your cat will recover and be healthy and hydrated again.