Why Is My Cat Urinating a Lot?

By Jane Meggitt

If your cat has suddenly begun urinating more than usual, he could have a serious disease. Polyuria, the technical term for excessive urination, is often accompanied by polydipsia, excessive water consumption. Various conditions cause polyuria, many with similar symptoms. Your vet must conduct tests to get to the bottom of Kitty's ailment. Take your cat to the vet as soon as you notice a change in his urinary and drinking habits.

Feline Hyperthyroidism

Hyperthyroidism occurs when the cat's thyroid glands produce too much thyroxine hormone, throwing the cat's system out of whack. Besides polydipsia and polyuria, another symptom of hyperthyroidism is weight loss although the cat still eats ravenously. Affected cats might vomit and start looking unkempt. Blood tests can rule out other diseases. The amount of thyroxine in the cat's system confirms a hyperthyroid diagnosis. Your vet can prescribe methimazole to correct the situation, but your cat must remain on the drug for the rest of his life. Another option is to remove one of the two thyroid glands, if the hyperthyroidism results from a benign tumor. The gold standard is radioactive iodine therapy, a simple shot that destroys malfunctioning thyroid tissue. This requires taking your cat to a special facility where he can stay for a few weeks until he is no longer radioactive.

Diabetes Mellitus

Cats diagnosed with diabetes mellitus no longer properly utilize insulin, a hormone produced by the pancreas. Polydipsia and polyuria are classic symptoms of diabetes, along with weight loss in a cat who is always hungry. Your vet determines your cat is diabetic by the presence of excess sugar in the blood, in tests repeated several times. Your cat will likely require once or twice daily insulin injections for the rest of his life, as well as a diabetic diet.

Feline Immunodeficiency Virus

Feline immunodeficiency virus, the equivalent to acquired immunodeficiency syndrome in people, generally passes between cats via severe bites. Outdoor tom cats are most at risk. Besides frequent urination, symptoms include appetite and weight loss, oral inflammation, diarrhea, nasal or eye discharge and swollen lymph nodes. Your vet can confirm FIV with a blood test. There's no cure for FIV, but with good supportive care, an indoor life, a high-quality diet and regular veterinary checkups, an FIV-positive cat can live for several years. Odds are that he will eventually succumb to an FIV-related disease.

Urinary Tract Disease

Is your cat actually urinating more frequently or just spending more time in the litter box? It's possible he's suffering from one of many conditions that fall under the term "feline lower urinary tract disease." These include bladder stones, cystitis, urinary tract infection and urethral obstruction. FLUTD is a veterinary emergency. Your vet determines what is causing the problem via physical examination, blood and urine testing, and radiographs. Treatment depends upon diagnosis, although a cat with an obstruction might require immediate surgery to remove the blockage.

Kidney or Liver Disease

Increased drinking can indicate kidney or liver disease. Symptoms of the two conditions overlap, including appetite and weight loss, vomiting, diarrhea and depression. Your vet will conduct blood and urine tests on the cat, checking the kidney and liver levels, and also take X-rays. For either condition, treatment revolves around dietary changes, and your vet will likely prescribe special food for your cat. If your cat suffers from renal failure, your vet might show you how to give your pet subcutaneous fluids to keep him hydrated.