It's the most common endocrinological condition in cats. Go to google and
type in hperthyroidism +cats. There are tons of information about it on the
net.
Gail

There is a feline hyper-T support group on Yahoo that used to be a good
source of information.  I haven't been a member for some time now.
http://groups.yahoo.com/group/feline-hyperT/

L.

One of my cats has lived with this condition for years.  She gets one pill
per day and occasional blood tests to check whether the dosage should be
changed.  She had become bone thin but now has regained weight.

--
Barb
Of course I don't look busy,
I did it right the first time.

http://maxshouse.com/Hyperthyroidism_in_Cats.htm

Be sure to put your cat on methimazole (Tapazole) for a few months to access
his kidney function before considering a permenant cure such a radioiodine.
Hyperthyroidism can mask underlying kidney disease because it speeds up
renal blood flow.

When you start therapy, begin with a small dose to allow the cat to adjust
to the medication and so the kidneys can gradually autoregulate.  Smaller
initial doses will also reduce the chances of adverse reactions to the drug.

Best of luck,

Phil.

A word of warning; unfortunately I didn't research this properly when
my cat was diagnosed with hyperthyroidism. My vet said surgery was a
cure, but my cat died a few weeks later, having never recovered fully
from the operation. Unfortunately for the vet he appeared to have
struck lucky on previous occasions when he had removed both thyroid
lobes. In my cat's case, the hyperthyroid implantation into muscle
which, when it works, allows the cat to continue to maintain its own
calcium levels, didn't work.

To be honest I think my vet was absolutely gutted about this, and so
he should have been, but at least he showed it unlike other vets I've
seen in the past.

However, FWIW - if you do consider surgery for some reason, NEVER
consent for both lobes to removed at the same time.

John