Urinary Blockage in Cats

A urinary blockage occurs when there is an obstruction in the urethra, the tube that carries urine from the bladder to the outside of the body. When this happens it is difficult or impossible for a cat to empty the bladder, making it a life-threatening emergency. If your cat is having trouble urinating (see list below), do not delay in having him or her checked by your veterinarian.


Why Blockages Occur

Although both male and female cats can develop urethral obstructions, the urethra is particularly narrow in male cats as it must pass through the penis and this makes male cats more prone to urinary blockage. Regardless of gender, the signs in both male and female affected cats are the same.

The material blocking the urethra can comprise several things, including:

  • Small bladder stones
  • Mucus
  • Inflammatory cells
  • Urinary crystals
  • Blood clots
  • Bacteria (usually a plug of bacteria combined with inflammatory cells and proteins)

Signs of Urinary Blockage

Cats that are partially or fully blocked often show some or all of the following signs:

  • Repeatedly straining to urinate in or around the litter box. This is often mistaken for constipation and straining to defecate.
  • Producing only small drops of urine or none at all
  • Crying or howling in or around the litter box or in general
  • Licking at the genitals or around the base of the tail
  • Hiding/lethargy
  • vomiting and/or refusing to eat
  • Resenting being touched, especially around the abdomen

Cats can experience partial or complete urinary blockage and their signs can vary greatly. With a partial blockage, an affected cat may seem uncomfortable or in pain and spend excess time repeatedly going in and out of the litter box. An owner may notice urinary accidents around the house or find small puddles of urine (sometimes bloody) in the litter box or unusual places.

As the condition progresses to a full urinary blockage and the cat is unable to pass any urine, the signs become more intense and the cat may experience life-threatening complications. It is common for a blocked cat to vomit, lose its appetite and become extremely lethargic. If left untreated, the urinary blockage can lead to kidney failure and death within 24 to 48 hours.

If your cat is showing any of the above signs, see your veterinarian or go to the nearest emergency clinic immediately.

What to Expect at the Veterinary Visit

When gently pressing on your cat’s abdomen, your veterinarian may identify a large, firm and often painful bladder from which urine cannot be emptied manually. Once a urinary blockage is identified, emergency treatment and stabilization is required. Blood and urine tests will usually be recommended to help identify any underlying causes as well as complications associated with the blockage. Radiographs (X-rays) or ultrasound may be recommended to help identify urinary tract stones or other underlying issues.

Most importantly, an affected cat must have the blockage relieved, typically while under heavy sedation or general anesthesia. A urinary catheter, or tube, is threaded into the urethra to help dislodge the obstruction and re-establish urine flow. The urinary catheter may be left in for a period of one to several days depending on the severity of the obstruction and associated complications. Many supportive treatments may be given during this time, including IV fluids, pain medications and sometimes antibiotics or other medications to help keep the urethra relaxed to encourage urine flow.

Not all affected cats can be unblocked with a urinary catheter and some may require emergency surgery, although fortunately this is less common.

What to Expect at Home

The first few days after your cat returns home may be stressful as some straining to urinate and discolored urine may still occur. Some cats may re-block during this time so close monitoring is required and any concerns should be reported immediately to your veterinarian. Frequent veterinary rechecks are usually scheduled during this time.Getting an affected cat unblocked and through the emergency is just the beginning of managing this condition. Unfortunately, it is quite common for urethral obstructions to recur days, weeks, months or even years later.

After a urinary blockage, lifestyle changes may be necessary to help prevent recurrence of this life-threatening condition. Several factors have been implicated as potentially contributing to urethral blockage, including household stress and inadequate access to or intake of water.

The following are steps your veterinarian may recommend to help prevent a recurrence in the future:

  • Increase the amount of water your cat drinks. This “simple” strategy is strongly associated with a decreased recurrence of urinary blockage. 
  • Look at food and diet. Your veterinarian may recommend a modified diet or a prescription diet — possibly one that can help dissolve certain types of crystals or stones.
  • Enrich the environment. Making sure your cat feels safe and stimulated is an important way to help decrease or eliminate household stress. Enrichment often includes appropriate litter-box management as well as access to climbing structures, viewing and resting perches and scratching posts. Synthetic feline facial pheromones may help reduce stress and anxiety for some cats.

The prognosis for most cats affected by urinary blockage is better now than ever before. But the outcome depends on how early a blockage is detected and how well the cat responds to treatment. Don’t delay if your cat is having urinary signs — a few hours can make a huge difference!


This blog was written by McQueen Animal Hospital, an animal clinic (vet hospital/vet clinic) in Brampton committed to providing only the highest level of veterinary care to our beloved pets.