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FLUTD or Cats with painful urination

Feline Lower Urinary Tract Disease (FLUTD)
Feline Idiopathic Cystitis, Feline Urologic Syndrome

Feline lower urinary tract disease (FLUTD) is a frustrating and life-threatening urinary disorder that affects neutered male cats.

How is this diagnosis made?

  • Physical exam - history and exam findings are typically enough to make a diagnosis of FLUTD.

  • Blood work - cats with urinary obstruction are often dehydrated and can have life-threatening electrolyte abnormalities and build-up of urinary toxins that need correction. Recheck blood work is performed to monitor response to treatment.

  • Urinalysis - evaluation of the urine itself will help to diagnose crystals in the urine.

  • Abdominal X-rays - to evaluate the bladder size and check for bladder stones.

  • Abdominal Ultrasound - may be recommended to further evaluate the bladder and the kidneys.

  • EKG - cats with urinary obstruction can have dangerously high potassium levels in the bloodstream that cause the heart to have an abnormally slow rhythm.

What is the approach to treating a male cat with FLUTD?


Cats presenting with urethral obstruction require emergency urinary catheter placement performed under a brief anesthesia. Anesthesia facilitates passage of the catheter by relaxing the urethral muscles. The urinary catheter is sutured in place to allow for normal urinary outflow while the cat is stabilized. Aggressive IV fluid therapy is used to normalize the electrolyte levels and help remove the build-up of urinary toxins (BUN and creatinine). Cats are often hospitalized for 24-72 hours with a urinary catheter in place,and treatment with fluids, pain medication, sedatives, and urethral relaxants. Once recovered from the episode of FLUTD obstruction, cats may be discharged with medical management or scheduled for surgical treatment. Some cats will re-obstruct shortly after discharge and may need to return for additional medical treatment, or surgery.


What causes FLUTD in cats?


Cats with FLUTD develop urinary crystals, spasm of the urethra, and an inflamed bladder which produces excessive mucus-like material. This combination of crystals, mucus, and blood in the urinary tract creates plugs which obstruct the urethra and prevent normal passage of urine out of the penis.


What are the symptoms of a cat with FLUTD?


FLUTD cats present with a range of clinical signs all related to abnormal urination including:

  • Straining to urinate

  • Blood in the urine

  • Frequent trips to the litter box with minimal urine produced

  • Urination outside of the litter box

  • Yowling while urinating or straining

  • Excessive grooming of the penis

  • With complete urethral obstruction: lethargy, vomiting, weakness, death


Cats with complete urethral obstruction cannot pass any urine which is a medical emergency that needs immediate treatment. If the urethra remains obstructed for too long, pressure builds up in the urinary tract system and causes damage to the kidneys and the back-up of urinary toxins in the bloodstream. The pressure can be great enough to rupture the urinary bladder and spill urine into the abdomen. Cats can develop fatal complications within 24 hours of urinary obstruction. For this reason, cats with FLUTD signs should be evaluated by a veterinarian immediately.


Unfortunately, we do not completely understand the underlying cause for FLUTD, but it is most commonly seen in young to middle-aged, overweight, neutered male cats. Episodes of FLUTD are almost always associated with a stressful event or changes in the cat’s environment such as new pets, people, or living arrangements. The vast majority of cats with FLUTD do not have a urinary tract infection.

Medical Management of a FLUTD

Medical management of FLUTD cats is aimed at reducing stress, increasing hydration, and preventing urinary crystals. Successful medical management of FLUTD cats can be achieved in some cats with strict adherence to the medical care plan including:

  • Removal of environmental stressors

  • Stress management with anti-anxiety or sedative medications

  • Pain control during episodes of FLUTD with pain medication

  • Feeding a prescription diet to prevent urinary crystals and reduce stress (eg. Hill’s c/d Multicare Stress, Royal Canin Urinary Calm diet)

  • Increasing hydration by using canned diets and/or adding water to their meals.

  • Increasing access to litter boxes (2 litter boxes per cat)

  • Increasing access to water (additional bowls, fountain, add to each meal)

  • Medication to relax the urinary tract

Medical management is continued for the rest of the cat’s life in order to prevent relapses. Many cats can be successfully treated with medical management, however 40-50% of cats will have another episode of FLUTD within 1 year. We cannot predict which cats can be successfully managed and which will require surgery. Usually, medical management is used for the first 1-3 episodes of FLUTD before deciding to pursue surgical treatment. The Ohio State University Indoor Cat Initiative is an excellent resource for cat owners to learn ways to reduce stress in their environment.

Surgical Treatment of FLUTD

Size of the urethra in male cats is widest as it exits the urinary bladder and narrows significantly to less than 1mm once it reaches the level of the penis. Urinary obstructions always occur at this narrow area of the urethra within the penis. Surgical treatment is aimed at removing this narrow area of the urethra and creating a new opening in the urethra where it is wider in the “perineal” region. This surgical procedure is called a Perineal Urethrostomy or “PU” for short. The penis is amputated and the remaining urethra is sutured to the skin to create a new exit for urine that is much less likely to become obstructed. The surgical site is very sensitive and cats must be kept from grooming the area at all costs for 2 weeks after surgery. Cats have very rough tongues and can cause severe trauma to the surgical site if they are able to groom the area before healing is complete. Damage to the surgical site before healing often requires additional surgery to repair.


Perineal urethrostomy dramatically reduces the chances of life-threatening urinary obstruction in the future, but does not address the underlying cause of FLUTD.  Life-long medical management is still required after surgery, most important of which is feeding a prescription urinary diet and reducing stress. In rare cases, cats may still obstruct after PU surgery due to large urinary stones, or structure of the surgical site over time.  It is important that cats are seen by a veterinarian if clinical signs return after PU surgery,

FLUTD cats that have bladder stones as a component of the disease also require a cystotomy procedure to remove the stones from the urinary bladder.

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