Polydipsia and Polyuria in Cats
Polyuria refers to an abnormally high urine production in cats, while polydipsia refers to the animal's increased level of thirst. While serious medical consequences are rare, your pet should be evaluated to ensure that these conditions are not symptoms of a more serious underlying medical condition. Your veterinarian will want to either confirm or rule out renal failure, or hepatic diseases.
Polyuria and polydipsia can affect both dogs and cats, and can be brought on by a variety of factors. If you would like to learn more about how these diseases affect dogs, please visit this page in the PetMD health library.
Symptoms and Types
The most common symptoms of these medical conditions are an increase in urination, and drinking much more water than usual. There are generally no other attendant behavioral changes.
The primary causes of polydipsia and polyuria include congenital abnormalities, and those associated with renal failure. Congenital diseases can include diabetes, a decrease in steroid production by the adrenal glands, and some rare psychological disorders. Kidney diseases, meanwhile, can be due to a congenital defect, or can be linked to tumors, increased steroid production, increased thyroid hormone levels, and electrolyte or hormonal disorders.
Other potential factors behind polydipsia and polyuria are low protein diets, medications that are prescribed for removing excess fluid from the body (diuretics), and age. The younger and more active a cat is, the more likely it is that it will have intermittent increases in thirst and urination.
Your veterinarian will examine your cat to determine the true levels of thirst and urination by measuring water intake and urination output. A baseline of normal fluid levels (hydration) and normal urination will be established for comparison, and an evaluation will be performed to ensure that the increased thirst and urination are not signs of a more serious medical condition.
Standard tests will include a complete blood count (CBC), a urinalysis, and X-ray imaging to rule out or confirm any issues with the renal, adrenal, and reproductive systems.
Any other symptoms accompanying the increased levels of thirst or urination, even when appearing unrelated, will be taken into consideration during the final diagnosis.