Question about thyroid treatments in cats

My sister's cat Libby has been on thyroid meds for a couple years and according to the latest tests at the vets, seem to no longer be working for her. The vet recommended that Libby have the radioactive iodine therapy. I think there were some members here that had cats go through this treatment. If so, can you tell me what the treatment involved and approximate costs?

 

I assume they've tried to tweak dose? If she's giving the gel on the ear that is not as effective as the pill. Methimazole also interacts with a bunch of other medications if she's on anything else that could also be a factor.

Around here the i131 is 2-3k, as is the surgery to remove the tumor. The iodine therapy is curative but has it's own risks, requires isolation etc. I'll have to dig for some members to tag later

 

Charlie had I-131 treatment back in the day. It’s been quite a few years so hopefully someone will bobble along with more current info. It was a life- saver for Charlie, given his complex combination of medical issues. I actually wish I’d done it sooner. I truly believe the hyperT was the root of some of his other issues. Anyway, here’s what I remember …

He had to “pass” a couple of tests to ensure it was safe to proceed with the I-131. Treating hyper-T can unmask kidney issues, so Charlie had a technetium scan and GFR (glomelular filtration rate) test. I think there was blood work and probably urinalysis as well.

Once we were a “go,” he had to be off of methimazole for 10 days. This part was harder than I expected because Charlie was soooo hyperthyroid that he quickly reverted to hyperactivity, miserable attitude/behavior, and worsening symptoms of his other issues. I don’t hear too many other people talk about this timeframe being difficult, so maybe it was somewhat unique to Charlie.

He was then hospitalized and placed in an isolation ward (due to the radiation). The radioactive iodine was a single injection. He stayed for about 5 days until the radiation levels dropped to levels safe for discharge.

He was sent home with instructions to keep him away from other pets for 14 days, to handle him the least amount possible in that time, and to wear gloves when touching him or cleaning the litter box. They also sent me home with a dedicated trash can for Charlie’s waste and told me to put all of his used litter and supplies in that can, then to bag it up and throw it all away (including the trash can) in the end. I was even told to toss his food bowls, blankets, and litter box. [Edited to add: the garbage can was to be stored outdoors and kept for a period of time before disposal, maybe a month or two.]

Price back then was significantly less than what I was quoted recently. Cost can vary widely between clinics, but it’s important to ask exactly what the quote includes (bloodwork, hospitalization, etc) so you can compare the “all in” cost when making a decision. I also asked how many they’d done and how/what complications they’d encountered.
It seems that I-131 is much more commonly done now and more widely available, so that part is good.

I-131 is curative, and that part is such a relief. It was one of the only things we could “fix” for Charlie. We had to monitor his thyroid levels afterward as they went LOW for awhile (expected, per the vet), but the IM specialist didn’t want to supplement as she said most cats eventually normalize on their own and supplementing can slow/prevent the body from adjusting. I have no idea if that’s still considered standard procedure, but Charlie’s thyroid levels did get back to normal after a few months.

Would I do it again? Absolutely. In our case, it was a “Hail Mary pass to the end zone” but I believe it saved his life. Curing a disease is so much better than treating symptoms. Like I said, I only wish I’d done it sooner. The chance of unmasking kidney disease is sobering, but you do that anyway with the methimazole, and methimazole isn’t innocuous. The difference is that you can’t “take back” the radioactive iodine, so the kidneys are where they are in the end.

Good luck to your sister and let us know what happens.

 

First, have your sister join this group, Hyperthyroid Cats on Facebook. https://www.facebook.com/groups/42301610484 If she isn't on Facebook, it's worth joining just for the info this group has. Really.

After two years being treated with medicine, and our cat's thyroid levels still rising, we had the iodine treatment done.

The time before treatment when he had to be off his medicine was very difficult. His levels were sky high, and the poor cat was absolutely miserable with extreme hyperthyroid symptoms. But this is a necessary evil in order for treatment.

The treatment itself is easy--they give the cat a measured injection of the I131. The cat then has to stay at the facility until the level of radioactivity decreases below a set limit. This will depend on your state/country. Ours lets most cats go in 3 days. I know of other countries where they hold the cat for 2-3 weeks, until all radioactivity is gone.

You cannot visit your cat during this time. Each cat will be in his own little "cat condo" (as they usually call it). You can send your own blanket or other stuff with them, but you will not get it back (because it will be exposed to radioactivity.) We had hubby sleep on top of an old t-shirt for a week, so that it smelled like him, and sent that along.

When your cat comes home, he will still have a low level of radioactivity. So the instructions will be to avoid close, frequent, or prolonged contact with the cat. So no snuggling on your lap or sleeping with you, don't hold and carry them around, etc. Best if they don't sleep with other pets, too. This is because you/the other pets will then be being exposed to the low level of radiation. As people live many many years longer than cats, this is something they want you to consider, as any effects from your exposure will have decades to show up. If your cat's buddies are also old cats, probably wouldn't be a factor as they will pass long before a problem can develop. Many people find this "isolation" protocol difficult, and ignore it. Since we had very young cats also, 2-3 year olds who could live another 20 years, we chose to pay for a few extra days at the vet's to make sure our cat's levels were much much lower before bringing him home. It was tough to be away from him, but the place would call with daily updates, and we felt the increased safety for the youngsters and us was worth it.
You can still play with your cat and all, just best to do it with things like string on a stick and laser light pointers, stuff that keeps you a few feet apart, as that is all that is necessary to avoid any residual radiation.

His pee and poop will contain radioactivity, again, a very low level, so they instruct you to collect it all, and usually say hold it for 30 days (or up to three months, depending on where you are) then you can throw it out. By that time the radiation has disintegrated, and it's safe. You can do this by just having a small, covered, trash pail outside your house, or if in an apartment, in the farthest, most unused corner of the place or back of a closet. This is not powerful radioactivity, so keeping a few feet away or a wall or two between you and it is sufficient.

We were not instructed to throw out bowls or bedding or anything. If your cat sleeps 20 hours a day on the same cat bed, you might want to put it in isolation for a while after the cat is deemed "safe", just in case, but probably not necessary.

Occasionally, a cat goes HYPOthyroid after treatment, ours did, but that can be controlled very easily with thyroid medicine pills. Our cat gets his tiny pill twice a day, with breakfast and dinner, no problem. Inexpensive (have them give you a prescription to take to a human pharmacy, so much cheaper!). Will need occasional bloodwork to make sure he's still at a good level and that medicine doesn't need adjusting. No problem.

It IS very expensive, but when you consider the cost of treating hyperthyroid when you keep having to up the medication dose, it doesn't take long to even out the costs. And the I131 is a CURE. I wish we had just done it from the start.

 

Oh, cost can be anywhere from $1800 to over $3000, depending on where you are. Some places include the pre- and post- treatment bloodwork, some do not, so figure that into the total as well. It's hard to part with that much money right up front. But, for example, in our case we were spending $60 a month on the medication, plus a couple of hundred dollars for every round of bloodwork trying to get the medication level corrected (you need to have a full thyroid panel done when trying to regulate, not just the quickie in-house test), so it very quickly adds up to the cost of I131 treatment.

 

I've had 2 cats, one diabetic, treated with i131 and they were cured. Both cats had severe allergic reactions to the oral and transdermal medications so sending them for radioiodine treatment was the best and only choice. Hyper-T and the drugs used to treat it are very hard on the organs, particularly the heart and kidneys and if another cat were to develop it, I'd go straight to i131 without hesitation.

My cats were done some years ago and cost was around $1100 for the first one and $1300 for the second. I'm sure it's way more expensive now but for me would still be worth it. The facility that they went to was an emergency hospital open 24/7 with webcams so I could check on them anytime and each cat had a window with bird feeders outside. I brought an assortment of foods, a bed, an old worn t-shirt and a detailed list of instructions about what and when to feed, etc.

JL already covered a lot of what I would say and my experience was very similar. Both of my cats were there 3 days and sent home with aftercare instructions but the veterinarian who administered the i131 told me not to be overly concerned about most of them. I did not isolate them, just washed my hands after handling, didn't let them sleep near my neck and because we had another 13 or so cats, was extra vigilant about cleaning the litter boxes. Common sense stuff, really. We did have to save the litter for about 8 weeks before disposing. The first T-4 tests post treatment were a little low which I was told is common, but a few weeks later were perfectly normal. Both cats were around 12 when they were treated and both lived to their late teens.

i131 facilities listed by state: https://marvistavet.com/list-of-facilities.pml