Blood in cat urine: causes and what to do

Blood in cat urine, called haematuria, is a sign of lower urinary tract disease, not a disease on its own. The most common cause is feline idiopathic cystitis (FIC), a painful bladder inflammation with no single known cause that is closely linked to stress. Other causes are bladder stones and crystals, urethral plugs, bacterial infection, and less often injury or tumours. Most affected cats also pee more often, strain, cry in the litter box or pee outside it. The urgent case is a cat, usually male, that strains and passes little or no urine. That can be a blocked urethra, and Cornell says a fully blocked cat may die in less than 24 to 48 hours, so it needs a vet within the hour. A vet finds the cause with a urine test, then X-ray or ultrasound if needed. More water, wet food, clean litter boxes and a calm routine lower the risk. In Malaysia this is often searched as kucing kencing berdarah.

This is general information from a grooming and boarding team, not veterinary advice. A cat straining with little or no urine needs a vet now, not tomorrow.

When is blood in cat urine an emergency?

Go to a vet straight away, even at night, if your cat:

• Strains in the litter box and passes only drops or nothing, especially a male cat.
• Goes back to the box again and again without producing a clump.
• Cries in pain while trying to pee, or has a painful belly.
• Becomes quiet, refuses food, vomits or hides.

These are signs of a urethral obstruction. Male cats, neutered or not, block more often because their urethra is longer and narrower. When urine cannot leave the body, toxins and blood salts build up and can cause dangerous heart rhythm problems. Check the litter box. If a straining cat leaves no fresh urine clumps, treat it as a blockage.

A cat that still passes normal amounts of pink or red urine is not in the same danger, but it is in pain and should see a vet the same day or the next.

What causes a cat to pee blood?

Cause	Who gets it most	How urgent
Idiopathic cystitis (FIC)	Young to middle-aged cats, more often males, often stressed, overweight or indoor cats on mostly dry food	Vet within a day
Bladder stones or crystals	Any cat. Males are more likely to block	Vet within a day, emergency if blocked
Urethral plug or blockage	Male cats	Emergency, within the hour
Bacterial bladder infection	Older cats and cats with diabetes, thyroid disease, FIV or FeLV, or on long-term steroids	Vet within a day
Tumour of the bladder or urethra	Rare. Average age 9 years	Vet appointment
Injury, nerve problems, narrowing of the urethra	Uncommon	Depends on the cause

Sources: Cornell Feline Health Center, VCA Animal Hospitals and Merck Veterinary Manual.

Idiopathic cystitis is the diagnosis a vet reaches once tests rule out the other causes. Cornell and Merck both call it the most common cause in cats with urinary signs. Stress plays a large part: a move, building work, a new pet, a change of food or tension between cats at home. VCA lists being overweight, staying indoors, low activity, multi-cat homes, a mostly dry diet and a nervous nature as risk factors.

Stones and crystals are minerals that form in the bladder. The two common stone types are struvite and calcium oxalate. Small crystals and mucus can also pack together into a soft urethral plug, which is a common cause of blockage in male cats.

Bacterial infection is less common than many owners think. Merck says healthy adult cats do not generally get bacterial cystitis. It is more likely in elderly cats and cats with other illness.

How does a vet find the cause?

The vet starts with a physical exam and a urinalysis, a check of a urine sample under the microscope. If the urine test does not explain the signs, the next steps are:

1. Urine culture to look for bacteria and choose an antibiotic.
2. X-ray or ultrasound to look for stones, sludge and the shape of the bladder wall.
3. Blood tests to check the kidneys and blood salts, especially in a blocked cat.
4. Cystoscopy, a camera inside the bladder, in some cases.

Bring a photo of the litter box clumps and note how often the cat goes and how much it passes.

How is blood in cat urine treated?

Treatment depends on the cause:

• Blockage: the vet passes a catheter, usually under sedation or anaesthesia, then gives drip fluids to correct dehydration and blood salts. Cornell says hospital stays range from a few days to several weeks. Cats that block again and again may need surgery called a perineal urethrostomy, usually as a last resort.
• Idiopathic cystitis: pain relief, sometimes anti-spasm or anti-anxiety medicine, more water and wet food, and changes at home to cut stress. Merck's owner guide says signs usually settle in 2 to 7 days, but about half of cats have another episode within a year.
• Struvite stones: may be dissolved with a prescription diet. Calcium oxalate stones cannot be dissolved and may need flushing or surgery.
• Infection: antibiotics chosen from the urine culture, plus treatment of any illness behind it.

Do not give any medicine your vet has not prescribed.

How can I stop it happening again at home?

Cornell and VCA list practical steps that lower the risk:

• More water. Keep fresh, clean water out at all times. Merck notes that switching from dry to canned food adds water and makes urine less concentrated.
• Small, frequent meals and a healthy weight.
• Do not add urinary acidifiers to a diet without your vet. Cornell warns that too much acid harms the kidneys.
• Enough litter boxes: one more than the number of cats, large, with deep litter, scooped daily and emptied regularly. See our cat litter guide.
• A steady routine for feeding, play and rest, and a safe high or hidden spot to retreat to.
• Less conflict between cats: separate food, water, litter and resting places in a multi-cat home.
• Never punish a cat for peeing outside the box. It adds stress.

Prescription urinary diets help some cats, but Cornell notes there is no evidence that "urinary health" foods prevent the condition in general. Ask your vet before switching.

Can a cat with urinary problems be groomed or board at PGH?

Not while it shows signs. A cat that is straining or peeing blood needs a vet, and PGH may decline a pet showing signs of illness. Please tell us about any urinary history before you book, so we can plan the stay or groom around your cat.

A change of place and routine is a known trigger for cystitis. For a cat that has recovered and boards with us at the cat hotel, bring its usual food, as our hotel rules ask, so its diet stays the same, and any medicine or prescription diet from the vet. Each cat has its own air-conditioned room with litter and a scratching tree. Read how to prepare your pet for boarding before the stay.

For a vet near us, see vet clinics in Subang Jaya and USJ, or government vet clinics in Selangor. PGH is in USJ 21, Subang Jaya: how to get here.