My Polly cat has today been diagnosed with Hyperthyroidism. I have been given 2 weeks worth of Felimazole to give her then if her symptoms improve she will either carry on the tablets for life or we can have an operation. I have searched on here and read a couple of threads (bit worried about some of the side effects of the tablets now though) but can't find any info on the actual operation. The vet said Polly was only early stages, her symptoms are drinking a little more than usual and her heart rate was raised a little. I only took her to the vet because I thought something wasn't quite right with her behaviour in that she was hiding away sometimes and not coming in for breakfast straight away in the morning when usually she is waiting for me as soon as I get up. She seems a little depressed. Does anyone know how this disease would make a cat feel in themselves?