I would ask the vet for a copy of any papers or research studies using it in acromegalic cats. I wouldn’t want my cat to be a guinea pig. There have been several studies of trying medications used in human acros on cats, with poor results. All I could find for cats was it being used in one type of Cushings, and another reference to help prevent spraying. The type of Cushings is also caused by a pituitary tumour, but different type of tumour from the one that causes acromegaly. The side effects are also something to consider. I can point you to research and acrocats using cabergoline, which main known side effect is some cats have mild GI upset.
In the years I have been here, I have never heard of anyone using bromocriptine mesylate for acromegalic cats.
One option might be to email the diabetes remission clinic at the Royal Veterinary College. They are the world leaders in research on Feline acromegaly and also in touch with doctors treating human acros. I am sure they would know if any research has been done on that drug,
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