What it is
Urine carries dissolved minerals. When conditions in the bladder change, these minerals can come together into crystals, and the crystals into stones, from fine grit to small pebbles. Their rough surface irritates the bladder wall, which becomes inflamed and can bleed.
The real danger lies in the narrow tube that carries urine out of the body. Male cats have an especially narrow one, so a small stone or a plug of grit can stop urine from leaving at all. A blocked bladder keeps filling, and within hours the cat can become seriously ill.
Watch the litter box: the number and size of the clumps tell you a lot. A cat that sits in the box and strains with nothing to show for it should not be written off as constipated until a vet has checked.
Signs you may notice
- Visits the litter box again and again
- Strains with little or no urine
- Pink or bloody urine
- Cries while urinating
- Urinates outside the litter box
- Licks its genitals a lot
A cat goes back to the litter box again and again, strains, passes only a few drops or cries while urinating. The urine may be pink or red, and the cat may lick its genitals a lot.
When to see a vet
If your cat strains and passes no urine, a vet is needed immediately, day or night. For blood in the urine or extra trips to the litter box, contact a vet the same day.
This is general information, not veterinary advice. For your own cat's health, tests and treatment, see a vet.