New Diagnosis - Missy Is Hyper-T

My Mom went to visit my sister in California, for the first time is a
couple of years. The very first thing she noticed was how much weight
my sister's kitty, Missy, has lost. My sister claims that Missy eats
like a little piggy...but Mom was alarmed by how emaciated Missy
looks (Missy was always a 'stocky' kitty!) I urged my sister to take
Missy to the vet, because ravenous eating with significant weight
loss is so often a sign of hyperthyroidism. Missy has also suffered
from poor hair coat, and feline trichotillomania (hair
pulllling...clumps of fur!) for years. At the vet visit, Missy's
heart rate was incredibly increased. Lori asked if it was due to her
being stressed, and the vet said that it was too fast to be explained
away by 'white coat syndrome.' Her weight was 8.2 pounds....I'm
guessing that she was probably 11 or 12 pounds two years ago. My
sister called me with the results, and HOLY MISTER!!! she's
significantly hyperthyroid. Here are Missy's abnormal labs, normal
range in ( ):


Alk Phosphatase 142 (0-62u/L)
ALT (SGPT) 225 (28-100u/L)
AST (SGOT) 56 (5-55 u/L)
Sodium 157 (147-156 mEq/L)
A/G ratio 0.9 (0.4-0.8) not sure what this is
RBC 10.40 (5.0-10.0 million/uL)
HGB 15.3 (9.5-15 g/dL)
HCT 53.4 (29-45%)

T4 16.2 (0.5-5.8 ug/dL)

Missy is approximately 11 years old. My sister got her when she was
about 2 years old. I think this is only the second time she's been
to the vet since my sister got her, as she's always been healthy. My
sister normally is a very conscientious pet owner. She cared for her
other cat, Billy, through several years of CRF, and her dog, Bo, when
he was diagnosed with lymphoma. Perhaps the weight loss was
insidious enough that she didn't notice it as it was happening.

Missy has been started on Tapazole, 5 mg, 2 times a day (I wonder if
this is correct, or if she meant mcg? I will try to clarify this the
next time I talk to her.) From the little exposure that I've had to
infomation about Hyper-T (I'm a member of the CRF support group, as Cleo and Maggie are both CRF kitties), I'm under the impression that cats don't seem to tolerate Tapazole very well. What type of side effects does she need
to be on the lookout for. If I remember correctly, nausea and vomiting are usually the first signs of intolerance, am I correct? I'm a little concerned about Missy's elevated liver enzymes, as I believe thyroid medications can have a toxic effect on the liver in some cases....probably because it's metabolized by the liver. I've also told Lori to add some water to Missy's wet food, because she appears to be a bit dehydrated, according to the labwork.

Missy got her first pill this morning, and Lori reports that Missy is
incredibly easy to pill (yea!) I am going to send her some #3 and #4
gelcaps, so that she can put the pill inside, as I've heard that
Tapazole can be quite bitter. Missy is scheduled for a re-check in
three weeks.

I'm hoping that Missy is able to tolerate the medication, and that
she puts some weight back on. Lori lost Bo two years ago, and I
honestly don't want to have to think about how devastated she would
be if something happens to Missy.

Does anyone else have Hyper-T kitties? Any anectdotes that you care to share?

I'd love to ask for prayers that Missy is able to tolerate the Tapazole and begins to put on some weight. I know how well those TCS prayers and vibes work!

Kelli Jo

I wil ask my friend Edna. Her Cat had it years ago. I also wll ask my friend Cat her Husband is a Vet Tech. I do not know anything about Hyper Thyroid in Cats.

The 5 mg is correct, but that is a high starting dose--it used to be common, but most cats do better (and have fewer side effects on 2.5 mg twice per day. The twice per day is very important because Tapazole has a short half-life in the body. It's best to try to get the doses as close to 12 hours apart as possible for maximum benefit. My cat Spot tolerated Tapazole well--his initial T4 was around 10, and later it peaked at 44. Regardless, the dose that he tolerated best was 7.5 mg per day, usually split into a 5 mg dose and a 2.5 mg. dose. The initial T4 level doesn't seem to have a predictive effect on what dose they will do best on. Every cat is different, and some need as little as 1/8-1/4 of a pill twice per day.

The side effects can include nausea, vomiting, itchiness, and elevation of liver enzymes. My mom's cat is hyperthyroid and did not tolerate the medication due to vomiting and liver side effects. Sometimes the vomiting can be controlled with a medication like Pepcid AC--sometimes it goes away after a while, so this might be worth trying. In my mom's cat's case, the liver elevations prevented her from taking medications.

The best treatment for the disease is Radioiodine Therapy (also called I-131). It is expensive (usually between $1000 and $1500 depending on where you live), but it has a 95% cure rate--meaning that the benign tumor that causes the hyperthyroidism is destroyed and the cat is either hypothyroid or euthyroid (normal levels). Hypothyroidism is much easier to treat and less dangerous than hyperthyroidism, so the risk of treatment is usually worth it. If Missy tolerates the medication, it is still worthwhile to look into radioiodine--the medication treats but doesn't cure the disease, and it can be expensive in the long-term between the pills and the blood tests. Also, because the medication doesn't perfectly control the disease, the extra T4 can still cause some damage to the heart and other organs. Medication is a good option for those cats who can't have the radioiodine therapy.

Your advice about the gelcaps is perfect--I used those with Spot with great success. They are also helpful if other medications need to be given at the same time. Just make sure she is following them with water or food to help the capsules get into the stomach.

If your cat tolerates the Tapezole you can manage the condition medically for years. I've never liked the drug myself, as I've only ever seen one patient that tolerated it well for any significant length of time. Generally the signs of not tolerating the Tapezole are vomiting, decreased appetite and depression/lethargy.

Get her drinking, and maybe pop her with some SQ fluids to help her hydration. SQ fluids are pretty safe, if there is an excess she'll just pee them out.

Eleven is relatively young, so Missy has that working in her favor. Good luck with her.

The old treatment for Tapezole-intolerant hyperthyroid cats was to just surgicate them, as long as the vet could get the thyroid out without damaging the parathyroid. In recent years the surgery has fallen out of favor and I can't find a vet anywhere that will do it. This is a shame, because the surgery usually worked quite well - I once had it done on a 19 year old cat and she put her weight back on and was not bothered anymore by the condition. She had 3 more years of quality time.

Nowadays the treatment of choice is radioactive iodine. This involves a long hospital stay until the cat stops glowing in the dark and it's expensive, but the safety margin is better because it's a lot less invasive than surgery and there is no anesthesia.

If it were my pet, I'd find a vet who is familiar with the thyroidectomy and good at doing them. Then I'd nag him until he did it for me.

In most places, the hospital stay isn't very long--Spot only had to stay from Tuesday to Friday. I wouldn't opt for the sugery unless I had a very competant surgeon and radioiodine wasn't an option for some reason. Suregy has all the normal risks of anesthesia, plus the risk of damage to the parathyroids (which can cause hypocalcemia) and higher probability of not all the material being removed (which would mean the cat would stay or become hyperthyroid again). With radioiodine, there is no anesthesia and a higher success rate, plus it treats ectopic thyroid tumors (tumors that have moved to different areas in the body). If you choose surgery, I would strongly suggest finding a vet with a lot of experience, since it can be a very delicate procedure.

http://www.avmi.net/NewFiles/Hyperth...Links/020.html
http://www.avmi.net/NewFiles/Hyperth...Links/073.html

This site has a nice table with pros and cons:
http://www.peteducation.com/article....&articleid=218

Thank you for your replies. I am hoping that Missy will be able to tolerate the medication, at least for the time being, as my sister is currently unemployed, and wouldn't be able to afford the I-131. Although, I suppose if she isn't able to tolerate the medication....Lori will have to come visit "Sister Bank" or "Bank of Mom & Dad" and we will loan her the money to get it done. I certainly wouldn't want Missy to suffer.

Lori will have to come visit "Sister Bank" or "Bank of Mom & Dad" and we will loan her the money to get it done. I certainly wouldn't want Missy to suffer.

Click to expand...

We do thyroidectomy's at the clinic I work at, and in my 5 years [hahaha I guess not super long!] I've seen probably 5-8 of these done, all have been successful with no issues. In the long term, if she does tolerate medication, your sister will be spending money on medication all her life [which could be another 8-9 years] so in the long run surgery might be of more benefit because she wouldn't be buying meds all the time. Like you'd have a big chunk of expense, and then be done. The most recent one we did was on a 15 year old cat, and last I heard she's doing really well.

Sending and for MISSY... and a I know about missing the wt loss... Kandie was down to 8lbs right before her CRF diagnosis( ideal in her younger yrs 13-14)