There are several reasons for it, and stress is one of them.
cat coming out of litter box; what does it mean if there is blood in your cat's urine?
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Seeing blood in your cat's urine can be alarming. You may have noticed drops of blood while cleaning the litter box, or maybe your cat is having accidents in the house and you see a red tinge to the urine. As you can probably guess, it's not normal for cats to have bloody urine—this warrants a visit to your veterinarian, but it's not always an emergency. 

Urinary issues are pretty common in cats. In fact, Nationwide Pet Insurance lists bladder and urinary tract disease as the most common reason for feline veterinary visits in 2021. Blood in cat urine is a common sign of feline urinary tract issues. Here's what might be causing blood in your cat's pee and what you should do about it.

What Causes Blood in Cat Urine?

Blood in the urine is called hematuria. Sometimes you can see the blood—the urine will appear red or otherwise discolored. Other times, hematuria cannot be seen with the naked eye, but blood cells can be seen on microscopic evaluation of the urine. 

Blood in cat urine usually occurs when something damages the tissues of the urinary tract. The feline urinary tract is composed of several structures: 

  • Kidneys: Filter waste and toxins out of the blood and use water in the body to produce urine that flushes out waste
  • Ureters: Transport urine to the bladder
  • Bladder: Stores urine until full
  • Urethra: Tube where urine passes out of the body from the bladder

A problem in one or more areas of the urinary tract may lead to blood in a cat's urine. Even certain problems elsewhere in the body may lead to hematuria. Here are some potential reasons for bloody urine in cats.


Cats, like people and dogs, can develop urinary tract infections that affect the bladder or kidneys. These infections are usually caused by bacteria and lead to inflammation of the affected tissue, which will often bleed.

Urinary Stones

It's possible for cats to develop stones in the kidneys or bladder. These stones cause damage to the tissues of the urinary tract, which can result in bleeding.


Injuries to the body can result in damage to the sensitive tissues of the bladder. Possible traumatic events that may lead to a bladder injury include animal attacks and fights, falling from a height, or being hit by a car.

Tumors or Cancer

It's possible for cats to develop one or more tumors in the urinary tract that may or may not be cancerous. Or, the cat may have a form of cancer that is not a tumor but still causes destruction of the tissue in the urinary tract that leads to bleeding. 

Bleeding Disorders

There could be a problem with the body's ability to control bleeding or clot blood. This may cause bleeding in the urinary tract that comes out in the urine. Bleeding disorders can be quite serious but are, fortunately, uncommon in cats.

Pandora Syndrome

For many cats who develop hematuria and the associated signs of urinary tract issues, there's no known physical cause. In the past, vets used certain blanket terms to describe these types of urinary conditions:

Today, veterinarians and researchers sometimes use the term "Pandora syndrome" in place of the conditions listed above. It was coined by Dr. Tony Buffington when a 2011 study indicated that many cats with these types of urinary issues also have conditions related to their skin, heart, endocrine system, or behavior. The study suggested that all of these problems may actually have a single source: stress

The name is a reference to the Greek myth of Pandora, who was given a box by Zeus and told to never open it. But her curiosity won out and she opened the box, releasing all the evil and hardships of the world. For cats with Pandora syndrome, it's stress—rather than curiosity—that leads to their physical and behavioral conditions.

What to Do If Your Cat Has Bloody Urine

If you notice blood in your cat's urine along with severe pain or lethargy, contact a veterinarian for advice right away—waiting might create an emergency situation, like a urinary blockage

If your cat seems otherwise normal, look for additional signs of urinary issues, which may include:

  • Peeing outside the litter box
  • Frequent urination
  • Urinating small amounts at a time
  • Straining to urinate
  • Vocalization, especially while using the litter box (this may indicate pain)
  • Frequent licking of the genital area
  • Mucus and/or sediment in the urine
  • Blood in stool (may occur if the hematuria is caused by a bleeding or clotting disorder)

It's important to call your veterinarian if your cat has bloody urine—whether or not you notice other signs. It may not be an emergency, but your cat should be seen by a vet within a day or two.

The vet will discuss your cat's history and current signs, then conduct a physical examination. They may need to collect a urine sample to test the urine for abnormalities and perform other tests, such as blood work, X-rays, or ultrasound in order to get a full picture of what's going on with kitty.

Treatment for Blood in Cat Urine

Urinary conditions in cats can be difficult to diagnose and treat. Once a diagnosis is made, the treatment will depend on the cause of the hematuria.

Urinary tract infections are typically treated with antibiotics, and stones in the bladder or kidneys may require a special diet or even surgery. Your vet may also recommend a diet change for both of these conditions.

Treatment of traumatic injuries may include medications, hospital monitoring, and even surgery depending on the nature of the injuries.

If your vet suspects a tumor or cancer, further diagnostics may be needed (and may require referral to a specialist). Treatment may include surgery, chemotherapy, and/or radiation therapy depending on the type of tumor or cancer.

There are a number of bleeding disorders that can affect cats, each with different treatment recommendations. Your vet may refer you to a specialist for treatment.

If your vet rules out other causes of bloody urine, they may diagnose your cat with Pandora syndrome or FLUTD (depending on the term your vet prefers). The key to treating this condition is managing stressors in the environment. You may need to make several changes in your home to reduce stress and anxiety and provide feline enrichment, which may include:

Cats with severe anxiety may benefit from medications or supplements in addition to the enrichment steps above. Your vet may recommend a consultation with a veterinary behaviorist or certified animal behavior consultant to address your cat's anxiety.

Preventing Bloody Cat Urine

The best way to prevent urinary issues like hematuria in cats is to look after their mental and physical health. Be sure to bring kitty to the vet at least once a year for a wellness exam—your vet may discover a hidden health concern. Feed your cat a healthy diet (your vet can help you choose one) and monitor your cat's weight

You don't have to wait for your kitty to get stressed out before you begin providing more enrichment in the environment. Your cat's mental health plays a major role in his physical health, so why not make his environment as engaging and stress-free as possible?