polyuria and polydipsia in cats
Whoever came up with the phrase, “It’s a dog’s life,” really should have considered a cat’s life first. After all, my cats spend what seems like 23.5 hours a day curled up sleeping! How hard can that life be? They get up for breakfast and dinner, and if I want to find them in between meals, I simply look on (or occasionally under) my bed.
One place I rarely see my lazy cats, however, is at their water bowl. Cats actually get most of the water they need in a day through their food. That doesn't mean that they never drink water – in fact, cats are notorious for drinking water from the kitchen or bathroom faucet because they seem to prefer running water. But if you notice your cat frequenting the water bowl or you’re finding larger clumps of urine in the litter box, an underlying illness may be the cause.
Drinking a lot of water and producing increased amounts of urine is actually a condition veterinarians call polyuria/polydipsia (or PU/PD for short). Polyuria is excessive urination. In the cat, this is considered to be more than 23 ml. of dilute urine per pound of cat per day. Of course, you can’t be expected to actually measure the amount of urine your cat produces, but you will notice a marked increase in the size of the urine clumps in your cat’s litter box.
Polydipsia is an increased amount of water intake. Cats with polydipsia will drink more than 45 ml per pound of cat per day. In single-cat households, this is easy to quantify if you measure the water you put in the bowl each day.
Polydipsia is generally a direct result of polyuria. When your cat is making more urine than normal, the drive to drink more water increases. There are a few reasons for primary polydipsia, such as increased salt intake, increased calcium levels and a condition called psychogenic polydipsia, however. And don’t forget environmental factors! If it’s hot outside or your cat has just engaged in heavy exercise, expect her to drink a little more water than usual.
There are many, many causes of PU/PD in cats, but the top three causes are:
1. Kidney disease
Age, breed and reproductive status should be considered when trying to determine the cause of PU/PD. Young cats are more likely to have congenital disorders, such as kidney malformations or portosystemic shunts, while older cats are more likely to be affected by kidney insufficiency or hyperthyroidism. If a female cat is not spayed, your vet will also consider pyometra (or uterine infection) as a possible cause for PU/PD. Finally, Abyssinian, Siamese and Oriental Shorthair cats are prone to a kidney disease called amyloidosis, which leads to kidney disease, and Persian cats are more likely to have polycystic kidney disease as the underlying cause for PU/PD. Whatever your breed of feline friend, protecting your kitty with cat insurance from Petplan pet insurance can help manage the costs of treatment of PU/PD.
Noticing your cat at the water bowl for extended periods of time here and there is nothing to worry about. But if it becomes a pattern, call your veterinarian to get to the bottom of it.