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Cat Peeing Blood: What It Means — and Why a Blocked Male Cat Is an Emergency

An adult tabby cat crouches in a gray litter box, looking worried, with a few small pink-red drops on the white litter, a sign of blood in the urine. A water bowl sits nearby in a bright room.

You notice a pink tinge in your cat’s litter box—is your cat peeing blood? Perhaps there are a few drops of blood, repeated trips to the litter box, or your male cat keeps squatting and straining—but nothing comes out. What every cat parent should know about blood in cat urine, urinary blockage, warning signs, and when it becomes an emergency.

At a glance

Bloody cat pee, or a cat bleeding when peeing, is a sign, not a diagnosis. Possible links include bladder inflammation, urinary tract infections, bladder stones, injury to the urinary tract and other underlying conditions. Seeing blood does not by itself point to an infection.

A life-threatening urethral blockage is more of a danger for male cats, as the male urethra is longer and narrower than the female one. A blocked male cat may keep returning to the litter box, strain to urinate and pass only a few drops, or nothing at all. Straining is easily put down to constipation by mistake.

With a complete blockage, the kidneys cannot filter waste as well as they should, and potassium may build up in the blood. Too much potassium can disturb how the heart pumps. Act before the cat collapses or becomes unconscious; do not wait for that stage.

No one treatment suits every cat with bloody urine. The vet decides on care by finding the cause and, above all, by checking whether the cat is obstructed. Home care, or antibiotics followed by watching and waiting, is never the right plan for a blocked male cat.

Seeing Blood in Your Cat’s Urine? Don’t Ignore It

  • What hematuria means: The presence of blood in your cat’s urine is called hematuria, sometimes visible and sometimes only detectable through a urine test.
  • What blood in urine may look like:
    • Pink/red urine: Urine may appear with a pink or red tinge due to blood.
    • Orange or tea-colored urine: Dark or unusual urine color may indicate oxidized blood.
  • Blood drops after urination: Dribbles of blood after urination may also be noticeable.
  • Blood in urine is a sign, not a diagnosis.

It may be associated with bladder inflammation, urinary tract infections, bladder stones, urinary tract injury or other underlying conditions. Your veterinarian will need to identify the actual cause before recommending treatment.

What Can Cause Blood in a Cat’s Urine?

Blood in the urine can result from bladder inflammation, urinary stones, urethral plugs, trauma and other conditions.

  • Feline idiopathic cystitis (FIC): FIC is one of the most common causes of lower urinary tract signs in cats. It involves inflammation of the urinary bladder without an identifiable underlying cause. Affected cats may pass blood in their urine, urinate frequently, strain in the litter box or urinate outside it. Stress, environmental changes and inadequate water intake may contribute to flare-ups in susceptible cats. [1]
  • Urethral plugs: Urethral plugs are accumulations of inflammatory material, mucus and mineral crystals that obstruct the urethra. This is particularly concerning in male cats because their narrower urethra makes them more susceptible to blockage. Affected cats may repeatedly strain to urinate but pass little or no urine. [2]
  • Uroliths/urinary stones: Mineral stones can develop in the bladder or other parts of the urinary tract. They may irritate the bladder lining, causing bleeding, discomfort and frequent urination. Some stones can also obstruct urine flow and require urgent treatment, sometimes surgical intervention. [3]
  • Bacterial urinary tract infection: Although bacterial infections can cause blood in the urine, they are more likely to occur in older cats and those with underlying conditions, such as chronic kidney disease or diabetes. A veterinarian may recommend urinalysis and urine culture to confirm an infection before selecting appropriate antibiotics. [4]
  • Trauma: An injury involving the abdomen, pelvis or urinary tract may cause blood to appear in the urine. If blood is noticed after a fall, road accident or other traumatic incident, seek veterinary attention promptly. [1]
  • Neoplasia: Tumors affecting the bladder or other parts of the urinary tract are less common but may cause blood in the urine, particularly in older cats. [2]
  • Important pet-parent message: “Blood in the urine does not automatically mean infection.”
Infographic: What can cause blood in a cat's urine. Feline idiopathic cystitis (FIC), bladder inflammation with no identifiable cause that stress can make worse; urethral plugs of mucus and mineral crystals that block the urethra, particularly concerning in male cats; urinary stones; bacterial infection, more likely in older cats; trauma after a fall or road accident; and tumors, less common and more likely in older cats. Blood in the urine does not automatically mean infection.

Which Cats Are More Prone to Urinary Problems?

Sex: Why a Male Cat Peeing Blood Is at Greater Risk

  • Male cats are at greater risk of life-threatening urethral obstruction because their urethra is longer and narrower than that of females. [1] [5]
  • Both male and female cats can develop feline lower urinary tract disease (FLUTD), cystitis, urinary stones and hematuria.
  • Castrated male cats are not protected from urinary disease; body condition, hydration, diet and environmental factors can also contribute to risk.

Age

  • Middle-aged adult cats and overweight cats are commonly affected by FIC. [5]
  • Older cats are more likely to have other underlying causes, including urinary tract infection, urolithiasis, kidney disease or neoplasia, so investigation becomes particularly important.

Breed

Some breeds have reported associations with particular urinary conditions. [6] For example:

  • Persian and Himalayan cats have been associated with increased risk of certain urinary stone types, although individual risk varies. [8]
  • British Shorthair and other breeds may also develop urolithiasis; breed alone does not establish the cause. [9]
  • Mixed-breed cats can absolutely develop urinary obstruction and FIC—this is not a disease limited to pedigree cats.

Signs of Urinary Blockage in Cats

Urethral obstruction is the major emergency. A blocked male cat may:

  • Repeatedly visit the litter box
  • Strain to urinate
  • Produce only a few drops—or nothing
  • Cry, vocalize or appear restless
  • Lick their genital area excessively
  • Urinate outside the litter box
  • Become increasingly painful or withdrawn

A key warning: Owners may mistake straining for constipation.

Infographic: Signs of urinary blockage in cats. A blocked male cat may visit the litter box again and again, strain and produce only a few drops or nothing, cry or seem restless, lick the genital area excessively, urinate outside the litter box, and become painful or withdrawn. Owners may mistake straining for constipation.

Male Cat Urinary Blockage: Why a Complete Blockage Is an Emergency

When the urethra becomes completely blocked, urine continues to accumulate in the bladder, causing it to stretch and increasing pressure within the urinary tract. As the pressure rises, the kidneys become less able to filter waste products and maintain the body’s normal fluid and electrolyte balance.

One of the most dangerous consequences is the accumulation of potassium in the bloodstream (hyperkalemia). High potassium levels can interfere with the pumping activity of the heart, potentially causing life-threatening cardiac arrhythmias.

Do not wait until the cat becomes collapsed or unconscious.

Infographic: Why a complete blockage is an emergency. Urine keeps building up and pressure rises in the bladder; the kidneys become less able to filter waste and keep fluids in balance; and potassium rises, which can disturb the heart's rhythm. Do not wait until the cat becomes collapsed or unconscious.

Diagnosis: Finding Out Why Your Cat Has Blood in Its Urine

A veterinarian may recommend several tests depending on the cat’s age, clinical signs and whether feline urinary obstruction is suspected.

Blood Profile

  • Complete blood count: looks for anemia, inflammation and other systemic abnormalities.
  • Serum biochemistry: evaluates kidney parameters such as BUN and creatinine, along with other parameters.
  • Electrolytes: particularly potassium, which can become dangerously elevated in a blocked cat.
  • Blood glucose may also be assessed depending on the clinical situation.

Urine Examination

  • Blood and protein: May indicate bleeding or inflammation within the urinary tract, although other conditions can also cause these findings.
  • Urine specific gravity (USG): Indicates how concentrated the urine is and helps assess the kidneys’ ability to concentrate urine.
  • Urine pH: Provides information about acidity or alkalinity, which can influence the formation of certain urinary crystals.
  • Glucose: May help identify glucose in the urine, which can be associated with diabetes.
  • Urinary sediment: Microscopic examination can reveal red and white blood cells, crystals, casts, bacteria and other material.

Ultrasonography

Ultrasonography can help evaluate:

  • Bladder wall: Thickening, irregularity and other changes that may accompany urinary disease.
  • Bladder contents: Sediment, debris, blood clots and certain abnormal structures.
  • Urinary stones: Many bladder stones can be visualized, although detection depends on their size and location.
  • Kidneys: Changes in size, architecture or the collecting system that may indicate urinary or renal disease.
  • Other abnormalities: Masses, anatomical changes and certain signs of cat urinary tract obstruction.

X-ray/Radiography

Abdominal radiographs can help detect and locate radiopaque urinary stones, particularly those containing minerals that are readily visible on X-rays.

However, some stones are poorly visible or radiolucent on routine radiographs. Therefore, a normal X-ray does not exclude urinary stones. Ultrasound or additional imaging may be needed, depending on the suspected condition.

Treatment: It Depends on What Is Causing the Urinary Problem

There is no single treatment for blood in a cat’s urine. Your veterinarian will choose treatment based on the cause and, most importantly, whether the cat is obstructed.

If the Cat Is Blocked

  • Immediate stabilization with IV fluids and correction of dehydration/electrolyte abnormalities
  • Analgesia to control significant pain
  • Sedation or anesthesia when required for safe urinary catheterization
  • Urethral catheterization and flushing to relieve the obstruction
  • Monitoring of urine output, kidney values and electrolytes
  • Hospitalization may be required until the cat is passing urine adequately and is clinically stable

A blocked male cat should never be treated at home or simply given antibiotics and observed.

If Urinary Stones Are Present

  • Treatment depends on the type, size and location of the stone
  • Some stones may be managed with a veterinary therapeutic urinary diet when dissolution is possible according to the size of the stones.
  • Stones that cannot be dissolved and are causing obstruction may need surgical intervention.
  • Dietary management and increased water intake are advised to reduce recurrence risk

If Bacterial UTI Is Confirmed

Appropriate antimicrobial therapy is required, ideally guided by urine culture and sensitivity when indicated. Any underlying condition that predisposes the cat to infection should also be treated. Follow-up may be recommended in recurrent or complicated cases.

If the Cat Has Feline Idiopathic Cystitis (FIC)

Treatment is generally aimed at controlling pain and reducing bladder/urinary tract inflammation while addressing factors associated with recurrence. Depending on the individual cat, this may include:

  • Pain relief
  • Increasing water intake
  • Wet-food or veterinarian-recommended dietary strategies
  • Improving litter-box access and hygiene
  • Environmental enrichment and stress reduction
  • Maintaining a healthy body weight and encouraging activity

Antibiotics are not routinely indicated for FIC when there is no evidence of bacterial infection.

Can FIC Come Back?

Unfortunately, some cats experience recurrent episodes. Long-term management therefore focuses on treating the current episode and also on hydration, environmental management, appropriate nutrition, weight control and recognizing urinary warning signs early.

Common Factors That Can Contribute to Urinary Problems

  • Low water intake: Concentrated urine can increase urinary irritation and, in susceptible cats, contribute to crystal/stone formation.
  • Diet: An inappropriate or poorly balanced diet can affect urine composition and urinary health.
  • Mostly dry food: Provides less moisture than wet food, so encouraging water intake can be beneficial.
  • Obesity & inactivity: Associated with increased risk of feline lower urinary tract problems.
  • Stress: An important contributor in cats with feline idiopathic cystitis (FIC).
  • Poor litter-box management: Dirty, crowded or poorly placed litter boxes can contribute to urinary and behavioral problems.
  • Male sex: Male cats are particularly vulnerable to urethral blockage because of their narrower urethra.

Vet tip: Adequate hydration, a complete balanced diet, healthy body weight, clean litter boxes and stress reduction can all support urinary health.

What Studies Suggest

  • Multimodal environmental management: [7] For recurrent FIC, current evidence increasingly supports addressing stress, cat–cat conflict, litter-box setup, enrichment and predictable routines alongside medical treatment.
  • Higher-moisture therapeutic diets: [7] Therapeutic urinary diets, particularly when combined with increased dietary moisture, currently have some of the strongest evidence for recurrent FIC management.
  • Reconsidering routine medications: [7] Drugs such as prazosin and glycosaminoglycan supplements have been widely discussed, but current evidence does not establish routine benefit for FIC; a 2025 systematic review found insufficient evidence for several commonly used therapies.
  • Surgical options for recurrent obstruction: [1] Cats with repeated episodes despite appropriate medical management may be evaluated for perineal urethrostomy (PU), which changes the anatomy of the urethral outlet to reduce the likelihood of future life-threatening obstruction.
  • Better emergency management of hyperkalemia: [10] Recent research suggests that, in cats with urethral obstruction and hyperkalemia, prompt relief of the obstruction, IV fluids and calcium gluconate are key components of treatment. Additional potassium-lowering medications may not provide significant added benefit in every case, but treatment should be guided by the cat’s clinical condition, serum potassium concentration and ECG findings.

Key Takeaways

Bloody urine points to a problem but does not name it, and it is not proof of infection. Treatment can only be recommended once your veterinarian has found the real cause.

Because the male urethra is longer and narrower than the female’s, male cats are more likely to suffer a life-threatening blockage. Constipation is a common wrong guess when a cat strains.

Never manage a blocked male cat at home, and never just give antibiotics and watch. Get help before the cat collapses or loses consciousness.

Good hydration, a complete and balanced diet, a healthy body weight, clean litter boxes and less stress all help support the urinary tract.

Frequently Asked Questions About Blood in a Cat’s Urine

1. Is blood in a cat’s urine always a sign of infection?

No. Inflamed bladders, urinary stones, urethral plugs, trauma and other conditions can all cause bloody urine, and bacterial infection is just one of the possibilities. Urine testing may be advised by your veterinarian to find the underlying problem.

2. Can stress cause blood in a cat’s urine?

Yes. Stress is a contributor to feline idiopathic cystitis (FIC), which is a frequent reason for lower urinary tract problems in cats. A change in routine, tension with other cats or a home that does not suit the cat may set off flare-ups. Even so, other causes need to be considered before FIC is diagnosed.

3. Can cats have urinary problems even if they are eating and behaving normally?

Yes. Early signs can be subtle, for example frequent trips to the litter box, small amounts of urine or the odd trace of blood. A good appetite and normal activity are not proof that your cat is healthy.

4. Does finding crystals in my cat’s urine mean it has bladder stones?

No. A urine sample can show crystals when there are no stones, and stones can be present when no crystals are detected. Your veterinarian reads the urine test result together with the symptoms and imaging findings.

5. Can urinary blockage occur in female cats?

Yes, but complete urethral obstruction is far more common in male cats. A female that strains again and again without passing urine should also be seen by a veterinarian immediately.

6. Can urinary problems come back after treatment?

Yes. FIC and similar conditions can return, and certain cats keep forming stones or blocking again. Stick to your veterinarian’s advice on diet, water intake, changes to the home environment and follow-up checks.

7. What are the cat urinary blockage symptoms to watch for?

Watch for a male cat that keeps going back to the litter box, strains and passes only a few drops or nothing, cries, vocalizes or seems restless, licks the genital area a lot, urinates outside the box, or turns painful and withdrawn. Straining is often mistaken for constipation.

8. Can a blocked cat be treated at home?

No. Home treatment is not safe for a blocked male cat, and antibiotics followed by observation are not enough. Take the cat for care before it collapses or becomes unconscious.

Glossary

Catheterization: passing a thin tube through the urethra to relieve a blockage and let urine drain.

Feline idiopathic cystitis (FIC): inflammation of the urinary bladder in cats with no identifiable underlying cause.

Hyperkalemia: a high level of potassium in the blood, which can interfere with the heart.

Neoplasia: abnormal growth of tissue, such as a tumor.

Perineal urethrostomy (PU): surgery that changes the urethral outlet to reduce the chance of future blockage.

Urethral obstruction: a blockage of the urethra, the tube that carries urine out of the body, so urine cannot leave the bladder.

Urinalysis: laboratory testing of a urine sample, for example for blood, protein, concentration, pH, crystals and cells.

Urolithiasis: the formation of mineral stones (uroliths) in the urinary tract.

References

  1. Taylor S, Boysen S, Buffington T, et al. (2025). 2025 iCatCare consensus guidelines on the diagnosis and management of lower urinary tract diseases in cats. Journal of Feline Medicine and Surgery, 27(2).
    https://doi.org/10.1177/1098612X241309176
  2. Van Vertloo L. (2025). Merck Veterinary Manual. Lower Urinary Tract Disease in Cats.
    https://www.merckvetmanual.com/urinary-system/noninfectious-diseases-of-the-urinary-system-in-small-animals/lower-urinary-tract-disease-in-cats
  3. Van Vertloo L. (2025). Merck Veterinary Manual. Urolithiasis in Cats.
    https://www.merckvetmanual.com/urinary-system/urolithiasis-in-small-animals/urolithiasis-in-cats
  4. Brown SA. (2024). Merck Veterinary Manual. Infectious Diseases of the Urinary System of Cats.
    https://www.merckvetmanual.com/cat-owners/kidney-and-urinary-tract-disorders-of-cats/infectious-diseases-of-the-urinary-system-of-cats
  5. Cornell Feline Health Center. (2016). Feline Lower Urinary Tract Disease. Cornell University College of Veterinary Medicine.
    https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/feline-lower-urinary-tract-disease
  6. Van Vertloo L. (2025). Urolithiasis in Cats. Merck Veterinary Manual.
    https://www.merckvetmanual.com/urinary-system/urolithiasis-in-small-animals/urolithiasis-in-cats
  7. Macleod B, Laven LJ, Laven RA, Hill KE. (2025). Understanding the current evidence base for the commonly recommended management strategies for recurrent feline idiopathic cystitis: a systematic review. New Zealand Veterinary Journal, 73(4), 233–245.
    https://doi.org/10.1080/00480169.2025.2477542
  8. Thumchai, R., Lulich, J., Osborne, C. A., King, V. L., Lund, E. M., Marsh, W. E., Ulrich, L. K., Koehler, L. A., & Bird, K. A. (1996). Epizootiologic evaluation of urolithiasis in cats: 3,498 cases (1982–1992). Journal of the American Veterinary Medical Association, 208(4), 547–551.
    https://doi.org/10.2460/javma.1996.208.04.547
  9. Lekcharoensuk, C., Lulich, J. P., Osborne, C. A., Koehler, L. A., Urlich, L. K., Carpenter, K. A., & Swanson, L. L. (2000). Association between patient-related factors and risk of calcium oxalate and magnesium ammonium phosphate urolithiasis in cats. Journal of the American Veterinary Medical Association, 217(4), 520–525.
    https://doi.org/10.2460/javma.2000.217.520
  10. Maciorowski, S., Rozanski, E. A., DeStefano, I., & Verschoor-Kirss, M. (2025). Pharmacological therapy for hyperkalemia in feline urethral obstruction has no additional benefit over intravenous fluid and calcium gluconate therapy and prompt unobstruction. Journal of the American Veterinary Medical Association, 263(10), 1268–1272.
    https://doi.org/10.2460/javma.25.04.0258

Disclaimer

This article is for general information and is not veterinary advice. It is not a substitute for an examination by a veterinarian. Decisions about your cat’s health should be taken with a qualified veterinarian who knows your cat.

Authors

  • Dr. Moon

    Veterinary Surgeon | Small-Animal Surgery & Radiology

    Job Role :Author

    Bio: Dr. Moon is a veterinary postgraduate specialising in veterinary surgery and radiology, with focused work in reconstructive surgery and skin-flap techniques in dogs. She has strong experience in small-animal soft-tissue surgery, anaesthesia and emergency critical care, and has worked with veterinary clinics, NGOs and wildlife rehabilitation centres handling both domestic and exotic cases.

    Special Skills:
    Veterinary Oncology

  • Dr. Emily Carter

    Veterinarian (Companion-Animal & Avian Medicine)

    Job Role : Reviewer

    Bio: Dr. Emily Carter is a licensed veterinarian with over four years of experience in companion-animal medicine, exotic bird care and animal-welfare initiatives. She has worked with veterinary clinics and welfare organisations providing treatment, preventive care and nutrition guidance, and focuses on improving animal health through evidence-based veterinary practice and caregiver education.

    Special Skills:
    Veterinary diagnostics, animal nutrition planning, avian medicine, preventive pet healthcare, animal welfare programs.

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