Bladder stones in cats: how to avoid them

Bladder stones in cats have myriad causes. Some breeds are pre-disposed to this condition, diet has a significant influence, and older cats are more likely to get them. Cats can develop bladder stones at any age. Some types of stones are more likely to form at different lifestages. The risk of developing calcium oxalate stones, for example, increases as your cat ages.

What are bladder stones?

They are rock-like deposits of minerals, crystals and organic material in the bladder. Of varying sizes, they may rub against the bladder walls causing inflammation and even a blockage of the urethra, preventing your cat from urinated.

Minerals form the stones; the two most common are calcium oxalate and struvite.

How Can I Tell If My Cat Has Bladder Stones

  • Blood in the urine
  • Painful urination
  • Straining to urinate
  • Frequent urination
  • Genital licking or licking of flank
  • Chronic urinary tract infections
  • Urinary tract obstruction (especially in males)
  • Spraying of urine
  • Passing urine in unusual places

Sometimes cats with bladder stones show no clinical signs at all.

What Causes Bladder Stones?

  • Nutritionally imbalanced diet
  • Decreased water intake
  • Urinary tract infection
  • High concentration of magnesium, ammonium and phosphate minerals in the urine
  • Urine pH favorable to the formation of various crystals
  • Certain drugs and dietary supplements
  • Congenital liver shunt
  • Breed predisposition (Burmese, Persian, Himalayn breeds may be more at risk of calcium oxalate stones)


Your vet will use X-rays, ultrasound,  and urine tests to diagnose the stones and find out what caused them.

Treatment for bladder stones

  • Vet-prescribed diet (to dissolve stones and modify pH)
  • Increased water consumption
  • Flushing procedure (filling bladder and inducing urination)
  • Surgical removal of stones
  • Sometimes cats – more likely females, whose urinary tracts are not as narrow as the male’s – will naturally pass the smaller stones when urinating.

Your vet may recommend a urinalysis and urine culture several times a year to test for crystals and/or infection.

And if they aren’t treated?

Stones that go untreated may lodge in the urethra, causing a blockage. Some signs of a urinary blockage are vomiting, nausea, appetite loss and a hard, distended abdomen. This is an emergency situation and will become fatal if not treated immediately.