Hello Krazikat — We had a cat named Tinkerbell that was diagnosed with hyperthyroidism and CRF (kidney problems). We fought both diseases bravely for 4 and a half years, in April Tinkerbell passed away from liver and kidney failure. So you can say I have become an expert in these things, it does not hurt that I was a veterinary technician. =)
Anyways back your questions. With hyperthyroidism your kitty will be eating LOT and let her. What hyperthyroidism is when the body metabolism is going really fast and if there is not enough food in there diet then to maintain the metabolism the body starts using the muscle as food. That’s bad. Now the meds you were given from the vet will help. But it is kind of a guessing game as to how much methimazole to give since it depends on the cat. So let her eat a lot. The fact that she has kidney problems means that canned food is the best but if you are not there is continuously feed her then leave dry food at while you are gone. But try to increase the wet food if you can.
The reason why the vet mentioned to switch to kidney food is because of the protein content. A high protein content for a cat with kidney problems will only make the problems worse. So if your kitty does not like some of the kidney food out there, which is what happened with Tinkerbell. Just look for senior or mature adult cat food with the lowest protein content you can find.
I hope this helps if you have any more questions I would be happy to help. Oh yeah there are many yahoo groups about hyperthyroidism and CRF they can also help.
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