When a cat goes to the litter tray often, it is important to tell small, frequent urinations apart from the cat actually producing a larger total amount of urine. Small amounts can be seen with idiopathic cystitis, urinary stones or other irritation of the bladder and urethra, for example. Large amounts of urine can instead be linked to increased thirst and other diseases.
Look for blood, straining, crying, licking around the genitals and whether your cat starts peeing outside the litter tray. The clinical examination is often followed by a urine test, and sometimes blood tests or imaging are needed, depending on the symptoms.
Contact a vet if your cat suddenly starts peeing much more often than usual or seems to be in pain. If it makes repeated attempts to pee but nothing, or almost nothing, comes out, it is an emergency, especially in a male cat.