Feline Idiopathic Cystitis

Feline Idiopathic Cystitis (FIC) is the term used to describe a group of urinary tract symptoms in cats. These symptoms include bloody urine, straining to urinate (frequently going in an out of the litter box and/or posturing to urinate with little to no urine voided), urinating in unusual places, licking the urinary opening, vocalization, and sometimes even vomiting.  

There are many causes of Feline Idiopathic Cystitis but the most common presentation is a case where the cause cannot be determined (this is the meaning of the term “idiopathic”).  

  • 50% of cases are idiopathic and will not have a diagnosable cause.  It is important for your veterinarian to rule out more serious causes of urinary symptoms before a diagnosis of Idiopathic Cystitis can be made. 
  • 20% of cats will have bladder stones
  • 20% will have a urethral blockage (this can be life threatening)
  • 1-5% will have a true bladder bladder infection
    • This risk increases in older cats and/or cats with diabetes or chronic renal failure
  • 1-5% will have urinary tract cancer
  • 1-5% will have a combination of a bladder stone and infection

It has been shown that certain environmental and genetic factors can play a role in developing FIC such as:

  • Stress
  • Inadequate water intake resulting in excessively concentrated urine
  • Insufficient cartilage layer lining the inside of the bladder
  • Predisposition to urinary crystals
  • Young, male, overweight cats tend to be more predisposed to FIC

Once your veterinarian has ruled out serious medical causes, your cat will most likely be diagnosed and treated for FIC.  Treatment usually consists of oral pain medications such as an opioid, as well as administering an electrolyte-balanced solution under the skin once or several times per week, to help dilute the urine. Additionally, canned diets will likely be recommended to improve moisture intake.  Antibiotics are not indicated in the treatment of FIC unless a bladder infection is simultaneously diagnosed or suspected.  Please keep in mind that since stress is a potential cause of FIC, when you plan to go out of town, be sure your pet sitter is aware of the signs of FIC and has your veterinarian’s number readily available, so that treatment can be promptly implemented if needed. 

Once a cat has had an episode of FIC, they have an increased risk of having recurrent episodes. Due to the chronic inflammatory nature of FIC, male cats especially, also have an increased of developing a urethral obstruction which is a life-threatening emergency.  To best minimize the chance of another painful episode of FIC, the following recommendations should be considered:

  • Feed a canned food diet – Prescription Hills c/d is an excellent choice 
  • If your cat is overweight, institute a weight loss program with your veterinarian. There are great canned prescription metabolic diets to help promote a healthy weight
  • Allow access to plenty of fresh (preferably filtered) water.  Cats love drinking out of pet water fountains which can stimulate additional water intake.
  • Decrease environmental stress as much as possible. Try to identify if any other pet or family member in the house has a tendency to distress the cat. Try to identify stressful household or neighborhood noises including outdoor stray cats that come into your yard. 
  • Environmental enrichment can minimize stress by allowing choices for your cat in terms of where to play, rest, eat and eliminate. All cats should have an opportunity to play with their owner or other indoor cat. Cats should be able to freely move about the home. There should be access to a private rest area where other pets or people cannot disturb the cat. Scratching posts and window access should be available. Additionally, cat trees can provide excellent enrichment for cats. There should be a litter box for each cat in the house, plus one extra. Each cat should have their own food and water bowls. It is preferred to keep all litter boxes, bowls and resting areas away from noisy household appliances.
  • Feliway diffusers can be added to multiple rooms of the house.  These diffusers spread the scent of cat pheromones which can have a calming effect on many cats.
  • Adequan injections – Adequan is a prescription medication that contains the building blocks of cartilage called polysulfated glycosaminoglycans (PSGAG). Once your cat is established on a maintenance dose, simple monthly injections can be administered.  This medication can help promote a healthier bladder wall lining.  
  • For more information, visit:
    • The Ohio State University College of Veterinary Medicine Indoor Pet Initiative at www.indoorpet.osu.edu. 
    • Cornell Feline Health Center at www.vet.cornell.edu. 


Feline Idiopathic Cystitis, Wendy Brooks, DVM, DABVP.  From the VeterinaryPartner.com Pet Health Library

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