Cystitis in Cats

At a glance

About: Cystitis is an inflammation or infection of the bladder in cats.


  • Frequent trips to the litter tray
  • Straining to urinate
  • Blood in the urine
  • Genital licking
  • Urinating outside the tray

Diagnosis: A thorough physical examination along with a medical history. Presenting symptoms, urinalysis, bacterial culture and

Treatment: Dietary changes, increasing water consumption, antibiotics and in some cases medications. Emergency care may include catheterisation, fluid therapy, and surgery.


Cystitis is the inflammation and/or infection of the bladder and a common cause of lower urinary tract disease in cats.

It can precede or be secondary to urolithiasis (stones in the urinary tract) and can be acute (sudden onset) or chronic (long-lasting). Cystitis is a common cause of frequent and/or inappropriate urination in cats, particularly females.

There is a higher incidence of cystitis in female cats due to their shorter urethra which makes it easier for bacteria to ascend from the perineum into the bladder.


  • Feline idiopathic cystitis (FIC): No known cause although stress is thought to be a contributing factor.
  • Bladder stones: One of the most common causes of cystitis in cats, accounting for up to 15% of all cases.
  • Bacterial infection: More common in senior cats over ten years of age.
  • Diabetes: Diabetic cats are at greater risk of developing cystitis as higher levels of glucose and protein in the urine promote bacterial growth. Decreased white blood cell activity may also play a role.
  • Long-term use of steroids: Due to decreased immunity which makes the cat more vulnerable to infection.
  • Infrequent urination or holding on for too long: Cats may delay urination if they are stressed, avoid urinating due to poor weather (and reluctance to go outdoors) or have dirty litter trays, trays located in inappropriate areas. Holding onto the urine can cause it to stagnate, which can help promote the growth of bacteria.
  • Dehydration: Senior cats, in particular, often drink less water than they should, which also leads to concentrated urine, making a perfect environment for bacterial growth and crystal formation.


  • Straining to urinate, only letting out a few drops (if any) at a time. Straining in the litter tray can be confused with constipation.
  • Blood in the urine.
  • Excessive genital licking, way beyond normal self-cleaning.
  • Sudden halt in litter box usage.
  • Crying in the litter box. You may hear your cat crying near, around or in the litter box. This also involves the cat attempting to urinate and little or no urine is passed.
  • Urinating in places other than the litter box, such as the bath or floor.
  • Smelly urine due to infection.

It is extremely important to note that difficulty urinating is a medical emergency and you should take your cat to the veterinarian immediately. Failure to act quickly can result in death. If your cat can’t urinate, toxins quickly build-up, causing uremic poisoning.


The veterinarian will be able to give a tentative diagnosis based on physical examination and signs, such as straining to urinate and licking genitals. He will feel the bladder through the abdomen, the bladder may feel large, full and distended or it may feel small and thickened.

Diagnostic workup:

  • Urinalysis: A test of the cat’s urine may reveal concentrated urine which is alkaline, red blood cells, white blood cells, bacteria, and sediment.
  • Ultrasound: An imaging technique using sound waves to evaluate the internal structures. This can reveal thickening of the bladder and/or the presence of bladder stones or tumours (rare).
  • Bacterial culture: If bacteria is found to be present in a properly collected (urine should be collected via cystocentesis, which involves inserting a fine needle through the abdominal wall and into the bladder, to prevent contamination of the sample) urine sample then your veterinarian may choose to perform a bacterial culture and sensitivity to identify the type of bacteria. This enables your veterinarian to determine the best type of antibiotic to treat the infection.

Home treatment

Treatment depends on the cause and severity of the condition. Finding and treating the underlying cause if possible.

  • Increase fluids: This reduces the concentration of the urine. It is also beneficial to aim for a pH below 6.5. pH in a cat’s urine usually ranges from 5.5 to 8.0, but diets that result in < 6.5 decreases the chances of struvite crystals forming.
  • Diet: Eliminate dry food and switch to canned or raw. Dry food contains approximately 10% water, whereas canned or raw food contains approximately 70% water.
  • Urine pH: Try to feed a diet that keeps the urine pH below 6.5. Unfortunately, the long-term use of an acidifying diet does increase the risk of developing calcium oxalate urolithiasis.
  • Multimodal environmental modification (MEMO): Enrichment of the cat’s environment by making several changes which include the following: providing places to hide (preferably from a height to enable the cat to survey its environment), change to an unscented cat litter, provide enough litter trays (one per cat, plus one extra), scattered throughout the house, clean litter trays frequently (remove solids twice a day and replace all litter once or twice a week), provide plenty of toys and schedule playtime, address and resolve inter-cat conflict and switch to a wet diet.

Medical therapy

  • Fluid therapy: Administration of fluids will help flush out the cat’s urinary system (particularly the bladder) and correct electrolyte imbalances.
  • Cystocentesis: A routine veterinary procedure with the use of a needle and syringe that is inserted through the abdominal wall to remove uncontaminated urine directly from the bladder.
  • Catheterisation: This is the system by which a catheterisation needle is inserted into the Cephalic vein in the front leg of the cat. After the intravenous needle is placed in the front leg of the cat it is wrapped. A urinary catheter is also placed in the cat’s urethra. This helps re-hydrate the affected cat and also helps flush out the crystals that have formed, as well as the excess potassium. Catheterisation on a cat takes place while the cat is under anaesthesia.
  •  Perineal urethrostomy (PU): A procedure for male cats who experience repeated bouts of cystitis or blockages. PU involves a partial amputation of the penis to the point where the urethral opening is larger. This will help reduce the risks of blocking, although it is still possible a small number of cats will become blocked even after the perineal urethrostomy.
  • Antibiotics: To treat bacterial infection. A culture and sensitivity can help to determine the most effective antibiotic.
  • Amitriptyline: A tricyclic antidepressant (TCA) used to treat behavioural conditions in cats which include excessive grooming, spraying, urinating outside the litter box, pica and anxiety.
  • Corticosteroids: To reduce inflammation in cats with idiopathic cystitis.


  • Keep stress to a minimum. This includes providing your cat with a well-defined schedule, cats don’t like change.
  • Don’t change types of cat litter suddenly. Cats like routine, if you make sudden changes your cat doesn’t like, they may either find another place to go to the toilet or hold on to their urine until they are desperate. It is far better for your cat’s bladder and urinary tract health if they don’t do this.
  • Make sure there are enough litter trays in your home. A rule of thumb is one tray per cat, plus one extra. So if you have two cats, you should three trays. Remove solids from litter trays twice a day and replace them with fresh litter once a week.
  • If your cat goes to the toilet outside, still provide an indoor litter tray so they can go to the toilet during rain or snow.
  • Provide plenty of clean, fresh drinking water, change at least once a day.


[1] The Cornell Book of Cats (p 227) – Edited by Mordecai Siegal.

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  • Julia Wilson, 'Cat World' Founder

    Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio

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