Senior cat with strange behavior/symptoms

by Lara
(New York, NY)

My senior cat (16 years old) has developed very strange cat symptoms/behaviors past couple weeks totally unlike her. She is extremely gentle & out of blue has attacked me in bed few times, and has been excessively biting and nipping. She is also hiding under bed, defecating all over the house, and spending a lot of crying.

Beyond the changes in her cat behavior, I also noticed that my cat had dilated, round pupils, very bad breath, and was twitching and sleeping fitfully. My cat’s appetite was decreased, and there was some vomiting, but her appetite picked up again. She does seem to have lost a lot of weight.

I took my cat to the vet yesterday, who said all looked okay, doesn't think it's a UTI, but that there is dental disease and big cavity in one of my cat’s front teeth. I'm waiting for bloodwork and urinalysis results, but wonder if you have any ideas. I am so attached to her & am beside myself right now. Do you have any ideas/suggestions in the meantime? Thank you for any advice you can offer.


Dear Lara,

Did your veterinarian offer any comments or provide any thoughts on your cat’s dilated pupils? Especially considering her age, dilated pupils can indicate loss of vision, which can, of course, disorient and cause behavior changes in cats. A loss of vision could also come secondary to a number of elderly cat health problems.

Common senior cat problems include feline hyperthyroidism, which can cause the symptoms you described and the changes in your cat’s personality as well, kidney disease, and cat diabetes. Any of these cat health conditions can contribute to poor dental health as well.

You did not mention whether your cat is exclusively an indoor cat or whether she does go outside? Bad dental disease in any cat can cause pain and make a cat not eat and lose weight, as well, although this sounds like more than that. But the relevance of whether your cat goes outdoors is that bad breath and/or dental disease for a cat that goes outdoors can be symptoms of FeLV/FIV. If your cat does go outside, she should be tested.

I wish I could do more to reassure you, but only the results of your cat’s bloodwork will really provide the information you are looking for. Please take comfort in knowing that you are doing the right thing. Try to keep in mind, during the painful wait for your cat’s test results, that many senior problems can be easily treated with feline medications and/or diet changes.

If you would like to write back with your cat’s results, I’d love to have an update.

All the best,
Dr. Neely