When urinary infections cause crystals and mucous to form in the urine, females can pass the crystals relatively easily. Male cats have a urethra that is longer and narrow.

Some will also notice the cat is in pain and licking excessively, but litter box problems are much more common. Not all cats with urinary tract symptoms like straining have an infection, however.

Crystals can be present in the urine, as well as mucus, and a large amount of blood. A dangerous sequelae of this disease is when those crystals/mucus/debris form a clot that lodges in the urethra.

Cats like to drink from running water; and good water intake helps to flush the urinary tract making crystals or a plug less likely to form, and helps to reduce inflammation along the bladder wall.