Changes in your cat’s litter box habits, especially repeated trips to the litter box, straining, or signs of discomfort, can signal a serious underlying problem. Urinary blockages are a life-threatening emergency in cats and require immediate veterinary care.

At VERC, we frequently care for cats with urinary blockages, and we understand how stressful this situation can be for pet parents. Our emergency team is skilled at diagnosing and relieving blockages as safely and comfortably as possible, while providing close, compassionate monitoring during recovery. When cats are brought to us promptly, many recover well and return home feeling much better.

Understanding what a urinary blockage is, which signs to watch for, and when to seek emergency care can make a critical difference for your cat’s health.

What Is a Urinary Blockage?

A urinary blockage happens when a cat cannot pass urine out of the bladder. Something physically blocks the urethra (the narrow tube that carries urine from the bladder to the outside of the body), so urine backs up, and the bladder keeps filling, like a water balloon.

Urinary blockage is most common in male cats because their urethra is very narrow, but can occur in females.

Why Is a Urinary Blockage So Serious?

When urine can’t leave the body:

• Toxins that are normally removed by the kidneys build up in the blood

• Potassium levels rise, which can cause dangerous heart rhythm problems

• The bladder becomes extremely painful and overstretched

• Without treatment, a blocked cat can collapse and die within 24–48 hours

Because of this, a urinary blockage is considered a true veterinary emergency.

What Causes a Blockage?

A blockage can be caused by:

• Crystals or stones

• Mucus plugs

• Inflammation or swelling of the urethra

• Muscle spasms of the urethra

Often, it’s a combination of these factors rather than a single stone.

What Signs Should Owners Watch For?

Cats with a urinary blockage may:

• Strain in the litter box with little or no urine produced

• Cry out or seem painful when trying to urinate

• Visit the litter box repeatedly

• Lick the genital area

• Act lethargic, hide, vomit, or stop eating

If a cat is straining and not producing urine, this should be treated as an emergency.

Straining vs. Constipation

Cats with urinary blockages can sometimes appear constipated. They may squat repeatedly and strain while producing little to no urine. You may also notice discomfort, vocalizing, or restlessness. Because these signs can resemble constipation, the situation can be confusing. When in doubt, it is safest to assume the straining is a urinary issue and seek veterinary care immediately.

How Urinary Blockages Are Treated:

Treatment requires immediate veterinary care and may include:

• Relieving the blockage with a urinary catheter

• IV fluids to correct dehydration and electrolyte imbalances

• Pain control and medications to relax the urethra

• Hospitalization for close monitoring

The sooner treatment begins, the better the outcome.

Can Urinary Blockages Be Prevented?

While not all urinary blockages can be prevented, certain steps may help reduce the risk:

• Encourage hydration: Feed canned food, add water to meals, or use a pet water fountain

• Reduce stress: Provide enrichment, predictable routines, and safe spaces, as stress plays a significant role in feline urinary issues

• Keep litter boxes clean and easily accessible

• Follow dietary recommendations: Cats with a history of urinary issues may benefit from a prescription urinary health diet

If your cat has experienced a blockage before, talk with your veterinarian about long-term management and warning signs to watch for at home.

When in Doubt, Get Help

If your cat is straining in the litter box, producing little or no urine, crying out, or acting painful, do not wait to see if the signs improve.

The most important takeaway:

If you ever think your cat may be blocked and is not passing urine, do not wait to see if it improves. Seek veterinary care immediately.

VERC has the equipment, experience, and continuous monitoring capabilities needed to safely treat blocked cats and respond quickly if complications arise.

VERC is open 24/7 and ready to help.

Call us at (808) 735-7735 or bring your pet to VERC, 345 N. Nimitz Hwy, Unit C, Honolulu. Our 24/7 emergency and critical care team provides advanced diagnostics, emergency surgery, intensive monitoring, and post-operative support.