Join Date: Apr 2012
Location: indoors most of the time
my first cat died when he was 17. i took him to the vet for blood work three times in a year, and they kept telling me his t-4 level was normal.
i didn't know to ask what it should be. i now have one who's 16, and she was diagnosed with hyperthyroidism 2 1/2 years ago. at first her level was 13 (normal is .08 - 4.0) and after three months it went down to 2.1. however, about 18 months into it, her level went back to 4. he still said it was normal, but i've found out that in medicated cats, it should be closer to 2.0. he okayed me increasing her dosage and she's fine.
eating a lot but losing or at least not gaining weight, and acting agitated or hyperactive (meowing a lot, trying to go outside if he didn't before, etc.) vomiting, and i forget what else, are signs of (but not limited to) hyperthyroidism so you might want to ask what his is, and if it's over 2.0, see if your vet thinks medication would be appropriate. diotima started to lose weight again at 4.0, so even though it's in the normal range, it was too high for her.