Hyperthyroid cat
 

My 13 year old male cat Harpo was just diagnosed with hyperthyroidism. His
node is palpable and his T4 is high (4.7), but his blood pressure and all
other blood work are fine, and he's not really showing any symptoms yet.
He drinks water a bit too frequently at night, but not during the day, so
I'm not really sure if he's drinking excessively or not. My hunch is that
this is the first indication that symptoms are beginning to develop.

When it's time to start treatment, I'm trying to decide between methimazole
or I-131. With the pills, I worry that we'll have to keep increasing the
dosage over time and have to do the I-131 anyway. But I worry that if I do
the I-131 now, when his T4 isn't off-the-charts high, I would risk making
him hypo-T. Is there a danger to doing the I-131 too soon?

I'm leaning towards putting him on the pills, and if they work without bad
side effects, stay with that unless the T4 keeps increasing or symptoms get
worse. Then do the I-131.

Does that sound like a good plan? Or is there a danger to staying on
methimazole for long periods of time? And does I-131 become more risky as
the cat gets older?

I obviously won't do anything without my vet's advice, but any thoughts
from the group are much appreciated. Thanks.

Hyperthyroid cat
 

"JEP" wrote in message
.130...
My 13 year old male cat Harpo was just diagnosed with hyperthyroidism.
His
node is palpable and his T4 is high (4.7), but his blood pressure and all
other blood work are fine, and he's not really showing any symptoms yet.
He drinks water a bit too frequently at night, but not during the day, so
I'm not really sure if he's drinking excessively or not. My hunch is that
this is the first indication that symptoms are beginning to develop.

When it's time to start treatment, I'm trying to decide between
methimazole
or I-131. With the pills, I worry that we'll have to keep increasing the
dosage over time and have to do the I-131 anyway. But I worry that if I
do
the I-131 now, when his T4 isn't off-the-charts high, I would risk making
him hypo-T. Is there a danger to doing the I-131 too soon?

I'm leaning towards putting him on the pills, and if they work without bad
side effects, stay with that unless the T4 keeps increasing or symptoms
get
worse. Then do the I-131.

Does that sound like a good plan? Or is there a danger to staying on
methimazole for long periods of time? And does I-131 become more risky as
the cat gets older?

I obviously won't do anything without my vet's advice, but any thoughts
from the group are much appreciated. Thanks.

JEP, I went through this a few years ago with our cat Boo.I wanted to do the
radioactive iodine treatment for her, but she had other conditions that
prohibited it. (We did not catch hers early and she had already developed a
heart condition.) Phil posted a lot of helpful stuff, if it is still
Googleable, that is the best place for you to go. The gist of it is,
hyperthyroid can rev the system up to the point that it masks renal or liver
malfunction--if I have it right--so before the iodine treatment, I believe
Phil said you should treat with Tapazole/methimazole to control the hyper t
and then check liver and kidney function to make sure they are such that
your cat can withstand the iodine treatment okay.

If I did not get that right, somebody correct me.

Boo did fine on pills for three plus years, but succumbed to oral cancer
last march at age 14. At 10-11, she was fairly young for hypothyroid, and
she was also an obese hyperT cat, which is rare. We did get her down to her
ideal weight, for what that is worth. Incidentally--symptoms may also be
howling for no reason and hypervigilance. A wide-eyed, hyper alert state
that may seem very un-cat like.