Hi there.
Thyroid problems are quite common in elderly cats.
My cat aged the same as yours had thyroid problems last may.
She was put on tablets to slow the heart rate down and she had a blood test too.
After a couple of weeks when the heart had slowed down to it's normal pace we decided to have the operation to remove the thyroid. If the thyroid is not removed we were told she would be on tablets for the rest of her life.
I didn't like the thought of giving her tablets everyday has she really hates them!!
After the operation we had to have another blood test to see if it worked and it did. She is now back to how she was and she has put weight on. The price of her operation was about £180.
Maybe ask the vet if an operation to remove the thyroid would be more beneficial for your cat.


Hope this helps.

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