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Crystals in Cat Urine

Rujuta Borkar Jul 29, 2020

The presence of crystals in your cat's urine can come about for a number of reasons that range from urethral obstruction to urinary stones. The following story will get into details about the same and explain how this condition can be treated.
Formation of crystals in cat urine is known as crystalluria or urolithiasis. It falls under the Feline Lower Urinary Tract Disease (FLUTD). Earlier known as Feline Urinary Syndrome (FUS), FLUTD is a serious cat illness that affects about 0.5% to 1% of cats. It is more common in males because they have a urethra that is narrower than that of the female cats.
These stones can be found in the kidneys, bladder, ureters (tiny tubes that carry urine from the kidneys to the bladder), or urethra (the tube from the bladder to the outside of the animal). These stones might also obstruct the outflow of urine. All in all, this condition is extremely painful.
The symptoms and formation of urine crystals include the following changes in the cat's behavior
  • Straining while urinating.
  • Urinating only 2-3 drops at one time.
  • Finding traces of blood in urine.
  • Sudden discontinuation of the usage of the litter box. 
  • Licking the genital region more than necessary.
  • Urinating rather frequently.
  • Crying around the litter box (which indicates that the cat wants to pass urine, but cannot.)
  • Urinating in other places other than the litter box.



The diet of the cat has a major effect on the formation of crystals in the urine. Whether a cat is allowed to eat throughout the day or whether specific meal timings are maintained, influences the formation of crystals to a great extent. A proper diet and timings of administering that diet will determine the urine pH levels, as well as the concentration of minerals in the urine; this will ultimately influence the formation of crystals.


FIC or Feline Idiopathic Cystitis is the most common cause for FLUTD in cats, and is seen to occur in over 50-65% cases. GP-51 is a glycosaminoglycan that lines the bladder of cats and protects them from the harmful properties of urine, and other forms of bacterial infections.
Cats who suffer form cystitis excrete lower levels of GP-51, thus causing the lining of the bladder to be exposed. Which ultimately leads to irritation of the urinary bladder, pain in the pelvic area, and formation of crystals in the urine.


Uroliths is another name given to urinary stones. Calcium oxalate or struvite crystals are the most common forms of urinary stone. Uroliths are found in 15-20% of cats suffering from FLUTD. A vet uses an ultrasound to determine the kind of stone that the cat has, after which, a proper course of action can be determined. It is possible for vets to treat these crystals in the urine by prescribing a diet that will dissolve the stones.

Urethral Obstruction

A urethral obstruction can prove to be fatal if not treated immediately. Urethral obstruction is usually caused by urethral plugs. These urethral plugs are made up of large amounts of protein (matrix) mixed with minerals. Some of these urethral plugs are composed of tissue fragments, circular debris, and blood cells. They may also have only matrix in them, or primarily contain crystalline minerals.

Other Reasons

  • Stress
  • Cancer
  • Trauma and anatomical defects of the urethra
  • Bacterial infection


Pain Control

Administering a pain control medication for your cat is essential because of the highly painful nature of this condition. An anti-inflammatory drug like carprofen will help reduce the pain.

Increase Water Intake and Change in Diet

An increase in water consumption will help dilute the urine and prevent crystal formation in the future. The water will help in producing more urine and therefore will help in flushing out the debris and crystals from the urinary tract. Make sure to give the cat as much water as possible.
Along with increasing the water content, switch to a more balanced diet for your cat that consists of natural raw meat instead of the wet and dry cat foods. The urine can thus maintain a more natural pH level.
Depending on the kind of stones that are formed, the diet will have to be administered. That is why it is necessary to form a diet plan in consultation with the vet.

Reduce Stress

Stress in cats can occur due to a change in diet, an introduction of a new cat in the household, or having to share things like food, and a litter box with another cat. As far as possible, allow the cat to have its personal space and provide separate things for it so that it does not lead to stress, and cause an eventual breakout of crystals in its urine.
As far as possible, try to replicate its most natural environment. Place scratch posts for them to trim their nails, and use toys and lasers to increase their physical activity. Cats who are sedentary have a higher risk of developing FLUTD and FIC.

Administer Antispasmodics

This will help in relaxing the bladder and urethra. Relaxing the walls of the urethra helps the cat in passing urine better and makes it a less painful ordeal. So also, an amitriptyline could be given to them. This is an antianxiety drug, so it helps calm anxious cats down.

Other Treatments

Give your cat glucosamine supplements to help build the protective glycosaminoglycan coating of the bladder. Similarly, urinary acidifiers can be given for the treatment of struvite crystals, and potassium citrate can be administered for the treatment of oxalate crystals.


Usually, a change in diet is administered as the first step in the treatment, but if the condition is severe, or the crystals have lodged into the ureters or urethra, then waiting for the stones to dissolve through a special diet is simply not possible.
In cases like these, a surgery needs to be undertaken and the stones physically removed to prevent the condition from turning fatal. Depending on the location of the stones, the type of surgery is determined.
After the stones are removed, the bladder and the urethra are flushed with a sterile saline solution such that it drains off any small or microscopic particles that may still be lodged there.
The presence of crystals in cat urine (as well as their passing), is a very painful condition, and can prove to be fatal if left untreated. It is due to this that the prevention of the condition is more important than the cure. In that direction, a proper diet has to be administered, and the most natural environment possible has to be maintained for the cat.