Dear Most Esteemed and Knowledgeable Kitties:

I have a cat that is 15 years old. I had her spayed 12 years ago. Right now, she has been in heat constantly for the past 2 months. She also has been urinating all over the house, mostly on my husband’s things. She has also been drinking a lot of water and is constantly hungry. She has never urinated on my husband’s things before. Any suggestions?

~Laurie

Siouxsie: We’re pretty sure that the behavior you’re witnessing is not your cat in heat.

Thomas: You’ve given us a couple of important clues about that. First, you said she’s been drinking a lot of water and is constantly hungry, and secondly you mentioned that she’s had behavior changes (acting like she’s in heat and urinating all over the place).

Dahlia: We think that your cat may be suffering from hyperthyroidism or diabetes. Both of these conditions will cause excessive drinking and hunger, and hyperthyroidism will cause behavior changes as well, and both of them are relatively common in senior cats.

Siouxsie: Has your cat been losing weight over the last couple of months? If so, it’s even more likely that your cat has one of these conditions.

Thomas: We’d strongly recommend that you take your cat to the vet and have him or her do a blood test. The blood test will show the levels of certain hormones and chemicals in the blood, and the cat’s blood sugar level. The results of the test will show if your cat has a metabolic disorder such as diabetes or hyperthyroidism.

Dahlia: The blood test will also determine how well your cat’s kidneys are functioning. Most cats lose some degree of kidney function as they age, and excessive thirst and urination are also signs of chronic renal (kidney) failure. A cat generally doesn’t go into renal failure until it has lost about 70% of its normal kidney function.

Siouxsie: If the blood test results are within the normal range, your cat may be suffering from feline cognitive dysfunction, also known as dementia. Senior cats with dementia start forgetting their toilet habits; they can also be seen sitting in a room looking confused, and often will have bouts of late-night yowling because they’re frightened and don’t know where they are.

Thomas: Any of the physical disorders we mentioned above can be treated and will allow your cat to enjoy a good quality of life for a bit longer. Hyperthyroidism is treated with a medication called Tapazole, which you rub into the skin on your cat’s ears. Diabetes is treated with a special diet and insulin shots. And chronic renal failure (CRF) can be treated by administering subcutaneous fluids.

Dahlia: There are more radical treatments available for two of these conditions: your cat could have a radioactive iodine treatment to reverse hyperthyroidism or a kidney transplant to restore function and temporarily cure CRF. However, most people don’t have the financial resources to undertake these treatments. And then there’s always the consideration that at age 15, your cat may be a poor surgical risk, particularly if she has a metabolic condition like CRF.

Siouxsie: If your cat has dementia, you’ll just need to be patient with her. If she howls late at night, call her name and tell her you’re right there. Make sure you have litterboxes at convenient locations, preferably near where she sleeps, so that she can easily find them when she wakes up and has to go. Your vet may offer a drug treatment that can decrease symptoms of dementia.

Thomas: Below are some websites containing information about the conditions we’ve described and some of the treatment options available:

• The basics of hyperthyroidism: Symptoms and treatment options (about.com cats forum)
• The basics of feline diabetes (from felinediabetes.com)
• What is feline chronic renal failure? (from felinecrf.com)
• Feline cognitive dysfunction, also known as feline dementia (from manhattancats.com)

Dahlia: We hope we’ve helped you understand what might be happening to your cat. Be sure to get her to the vet for a checkup and blood test!