Radioiodine treatment for hyperthyroidism

[david68]

I've been treating one of my cats for hyperthyroidism with methimazole for a couple of years, but her values keep climbing, so we're looking at radioiodine treatment. I've had lots of diagnostic tests run on her, including an echocardiogram and a thyroid ultrasound. She's 15, but still otherwise pretty healthy. It's expensive, but I don't have kids. The clinic claims 96% success.

Have any members here had radioiodine hyperthyroidism treatment? I'm slightly concerned about stress to her since she's never been away from home for more than a few hours. I guess I can take her with a t-shirt I've worn, and they can just throw it away after if they're worried about contamination. Any other ways to ease stress for a 4-5 day clinic stay?

 

[Antonio65]

Hi and welcome to the club of I-131 cats.

My cat was 16 years when she was treated with radio iodine. She was on methimazole for nearly a year before that, pills first and eargel next.
She didn't have an ultrasound to her thyroid, but we ran a blood test every 5 to 6 weeks, and we would adjust the methimazole dosage accordingly.

The facility where I took her for the treatment ran a scintigraphy so that they could give her the proper dose of radio iodine.
The success rate that they claimed was in excess of 97%.

My cat was extremely shy and she wouldn't handle being away from home well, but I didn't think of leaving some item from home with her. What I do know is that she hardly ate during those 5 days.
Leaving a t-shirt of yours is a wonderful idea, I think.
You won't regret having her treated with I-131. It's expensive, but it is worth every single cent.

 

[FeebysOwner]

Make sure you thoroughly investigate what needs to be done (including specific testing pre-procedure) before you move ahead, as well as who you are thinking about using. There are facilities that don't require as stringent protocols as others, so you can evaluate the differences. I don't know what all you have researched but will offer this web site for additional information (see link below).
Animal Endocrine Clinic | Where science and compassion cure

 

[david68]

Make sure you thoroughly investigate what needs to be done (including specific testing pre-procedure) before you move ahead, as well as who you are thinking about using. There are facilities that don't require as stringent protocols as others, so you can evaluate the differences. I don't know what all you have researched but will offer this web site for additional information (see link below).
Animal Endocrine Clinic | Where science and compassion cure

I've been through the timeline for testing pre-treatment both with the staff at the clinic and with my regular vet, including the need to take her off her methimazole for a time to get her non-medicated baseline. My vet thinks we can do that without significant danger, particularly since she shows no signs of cardiac changes from the hyperthyroidism.

 

[FeebysOwner]

I guess my main concern is whether or not a thyroid scintigraphy is part of that pre-treatment process. It has now become a big player in determining the appropriate I-131 treatment dosage in cats. Just mentioning it because I am not sure all groups use it routinely.
Do Hyperthyroid Cats Always Need a Thyroid Scan? | Animal Endocrine Clinic

 

[neely]

Have any members here had radioiodine hyperthyroidism treatment? I'm slightly concerned about stress to her since she's never been away from home for more than a few hours.

I completely understand your concern about stress since the specialty center we chose for our cat's I-131 treatment kept him there five days. I cannot stress enough how important it is to go to a hospital that uses Scintigraphy as the above two members mentioned. The staff at the hospital were extremely attentive, e.g. they called us several times a day with updates and said we could call as often as we wanted. They told us exactly what he ate and how much as well as how fond they were of him. When he came home we could not have close contact with him for two weeks. My husband and I thought it would be heartbreaking for us to wait the full amount of time before we could cuddle with him but I told myself if we were going to follow the specialist's instructions we would do whatever it takes for him to get well.

 

[david68]

I'm in North Carolina, and I'm not sure that any veterinary hospital in the state offers scintigraphy. I googled it and couldn't find anything. I'd never heard of it before. She has had a thyroid ultrasound. The bottom line is that I'm already spending more than I can afford. It's great that such services are offered where you live, but I can't fly her to New York City for this. That's not an option. It already costs $2,000, plus testing that has to be done beforehand.

 

[FeebysOwner]

Try seeing if you have a VCA facility in the area around you - many of them used to have the capability to perform a scintigraphy. This procedure aids in determining the level of iodine treatment so as to help avoid putting a cat into hypothyroidism. Hypo-T is correctable with meds, but that sort of defeats the point of the treatment in the first place.

NC State Vet Hospital in Raleigh might be another location to contact about scintigraphy, as well as if they have satellite locations should Raleigh be too far away.

 

[david68]

NCSU's website states; "Due to staffing limitations, we are currently not seeing any feline hyperthyroid patients for the I-131 therapy. We hope to resume in the fall of 2022. Please contact your primary Veterinarian’s office for options regarding this diagnosis."

But I'll check around.

 

[FeebysOwner]

NCSU's website states; "Due to staffing limitations, we are currently not seeing any feline hyperthyroid patients for the I-131 therapy. We hope to resume in the fall of 2022. Please contact your primary Veterinarian’s office for options regarding this diagnosis." But I'll check around.

You might actually call them just to make sure someone hasn't missed removing/updating that note on their web site. The least they could do is update it to reflect it is still in effect, nearly 3 quarters of a year after the date they have listed. Don't forget the VCA facilities.

 

[david68]

You might actually call them just to make sure someone hasn't missed removing/updating that note on their web site. The least they could do is update it to reflect it is still in effect, nearly 3 quarters of a year after the date they have listed. Don't forget the VCA facilities.

I'll call around in the morning, but if that doubles the cost, it's just not an option.

 

[FeebysOwner]

Do Hyperthyroid Cats Always Need a Thyroid Scan? | Animal Endocrine Clinic

 

[Furballsmom]

Hello - Here's my story, which is intended to give you an idea as to why I'm even mentioning it ....

My angel Poppycat had a compromised liver prior to being diagnosed with Hyperthyroidism so the medicine was not an option, and he was extremely stressed by normal vet visits so at 17 years old, the treatment was out.

We chose the dietary approach of Hills Y/D. Fortunately he liked their kibble, and they also have canned food. I worked out a feeding schedule where he got both wet and dry Y/D and also Weruva which at the time (early to mid last year, 2022) was the only commercial non-vet-scrip-needed food on the market with the lowest iodine levels that meet AAFCO requirements. Many other cat food brands don't pay any attention and their iodine levels can be amazingly, concerningly high.

To me, it's sort of like a fish tank, where if an aquarist's water source has high levels of chloramine, recommendations for water changes to keep the tank water parameters safe and healthy for the fish can be followed, but when that water source is awful (correlating to what the iodine levels might be in the cat food you are feeding her), ammonia is simply being added right back in to the tank and causing all sorts of unintended, bad issues.

In any case, would your vet consider a diet approach a possibility in conjunction with the methimazole (I have no idea if this is even a possibility), or instead of the methimazole, rather than the treatment you're currently considering?

https://www.chewy.com/hills-prescription-diet-yd-thyroid/dp/54583

 

[FeebysOwner]

In any case, would your vet consider a diet approach a possibility in conjunction with the methimazole (I have no idea if this is even a possibility), or instead of the methimazole, rather than the treatment you're currently considering?

From what I know, vets generally recommend an either/or approach with meds vs. diet. And, for the record, neither approach is a cure, nor will it stop the thyroid tumor from growing. The only cure is the radio iodine treatment. The thyroid tumor(s) can be surgically removed, but not sure that is a cure either.

 

[Furballsmom]

vets generally recommend and either/or approach with meds vs. diet

Makes sense, thanks for the clarification .

 

[neely]

I'll call around in the morning, but if that doubles the cost, it's just not an option.

I understand your concern and please know that we are only recommending Scintigraphy for the safety of your cat. If it helps I can tell you from my own personal experience it no where near doubled the cost but rather was included in the cost of the I-131 treatment which was under $2,000. The tests that had to be done beforehand were performed by our own vet who is a feline only vet.

 

[neely]

The only cure is the radio iodine treatment. The thyroid tumor(s) can be surgically removed, but not sure that is a cure either.

This is one of the reasons why Scintigraphy should be performed. If the tumor is too large or there are other potential problems the radiologist will not perform the I-131 but rather discuss removing the thyroid.

 

[Antonio65]

Do Hyperthyroid Cats Always Need a Thyroid Scan? | Animal Endocrine Clinic

Excellent link, thank you!

 

[david68]

You might actually call them just to make sure someone hasn't missed removing/updating that note on their web site. The least they could do is update it to reflect it is still in effect, nearly 3 quarters of a year after the date they have listed. Don't forget the VCA facilities.

Confirmed. NCSU Vet School's radioiodine program is "on pause" with no estimate of when it will resume.

 

[david68]

I've done some calling around. No one in North Carolina seems to know of any facility that uses nuclear scintigraphy for hyperthyroidism treatment. I'm certainly glad to know about it, but there's not a lot I can do to access a service that isn't available in my region. In fact, it seems like the number of facilities that offer radioiodine treatment for hyperthyroidism around here has declined. I called the local VCA based on their website, and they said that their site was outdated and that they were not doing it at this time. They referred me to the place in Carrboro where I already have an appointment.

But I did learn one thing in my reading: One site said that cats can become resistant to methimazole after using it for a while, and mine has been on it >2 years.