Hyperthyroidism in Cats

Draco

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So back in January-ish my cat was diagnosed with Hyperthyroid. and he's doing much better on his medication! Gained some weight and isn't as food aggressive.

I noticed recently the base of his tail is missing some fur and he's been flicking it. Reading up suggests it might be a part of hyperthyroid (he's got his follow up apt next month). And it got me wondering, what other symptoms are people experiencing with their cats and what did they do to help?

I am curious to how common certain side effects are of the medications, and how common certain symptoms are?

To those with experience, share what you've noticed with your cats' hyperthyroid? I want a little reference/database for lack of better terms and hear from you guys. Please share?
 

neely

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For our cat the most significant symptoms were weight loss despite an increased appetite, some vomiting and thirst. The methimazole definitely helped and we brought him to the vet regularly for T-4 tests. However, hyperthyroidism is known to mask other conditions such as high blood pressure, kidney disease and in some cases heart problems. All the more reason to monitor your cat's T-4. After nine months on methimazole we opted for the I-131 radioactive iodine treatment which had a good outcome for our cat. Although there are similarities in symptoms and side effects I think every cat is different, therefore, it's important to discuss this with your vet.
 

misterginja

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So back in January-ish my cat was diagnosed with Hyperthyroid. and he's doing much better on his medication! Gained some weight and isn't as food aggressive.
I wanted to thank you for starting this thread, I have no experience with this and am here to learn...my boy was just diagnosed hyperthyroid this week, and am trying to understand it. I hope your kitty's symptoms improve soon!
 

VinceL

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Over the years we have had 2 cats with hyperthyroidism and our daughter had 1 cat with it. They all experienced similar symptoms of losing weight yet eating a lot more. We tried the methimazole with the first cat. It helped for a couple of months. We went with the radioactive iodine treatment for him, and it worked out very well. It is important that the vet uses the correct dosage....too much and you can wind up with hypothyroidism. Fortunately, the vet we used nailed the correct dosage. A couple of years later, one of our other cats developed hyperthyroidism. We didn't even try the methimazole; we went directly to the radioactive iodine. Once again, the results were great. Both cats went on to live many more years.

After our successes, when our daughter's cat had hyperthyroidism, she also went with the radioactive iodine and had excellent results.
 

Alldara

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Lily's symptoms were excessive vocalizing, increased attention seeking, huge change in flavour preferences that reversed upon treatment, vomiting and weight loss.

Oral Methimazole treatment went well. We did a slow start and increased incrementally. I didn't particularly notice any side effects. Except she got sick with a URI after starting it and couldn't kick it despite months of medications. According to the vet we had at the time, methimazole does not lower the immune system and played no part in this. I have no clue if this was or is accurate information based on what was available at the time or updated research now.
 

IslandGirl242

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Over the years we have had 2 cats with hyperthyroidism and our daughter had 1 cat with it. They all experienced similar symptoms of losing weight yet eating a lot more. We tried the methimazole with the first cat. It helped for a couple of months. We went with the radioactive iodine treatment for him, and it worked out very well. It is important that the vet uses the correct dosage....too much and you can wind up with hypothyroidism. Fortunately, the vet we used nailed the correct dosage. A couple of years later, one of our other cats developed hyperthyroidism. We didn't even try the methimazole; we went directly to the radioactive iodine. Once again, the results were great. Both cats went on to live many more years.

After our successes, when our daughter's cat had hyperthyroidism, she also went with the radioactive iodine and had excellent results.
Thank you for posting the encouraging results with your cats.
 

misterginja

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After our successes, when our daughter's cat had hyperthyroidism, she also went with the radioactive iodine and had excellent results.
This is helpful to hear, would you be able to say if any of the cats also had kidney disease at the time of their I-131 treatment? Thanks...
 

VinceL

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This is helpful to hear, would you be able to say if any of the cats also had kidney disease at the time of their I-131 treatment? Thanks...
None of our cats had kidney disease at the time of the I-131 treatment. One of them did develop kidney disease, but it was at least 2 years after the I-131 treatment.
 

neely

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This is helpful to hear, would you be able to say if any of the cats also had kidney disease at the time of their I-131 treatment?
There are a series of tests and x-rays that have to be done prior to receiving the radioactive iodine injection which are reviewed by your vet and the radiologist performing the I-131 treatment. Unfortunately if the cat has any organ involvement they are not considered a good candidate for it.
 
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Draco

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Im not sure if I can ask, but how much did the Radioactive Iodine treatment cost? I am considering it but I don't think I can afford it right now. I will ask my vet about it anyway
 

neely

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Im not sure if I can ask, but how much did the Radioactive Iodine treatment cost? I am considering it but I don't think I can afford it right now.
Let me preface the cost we paid by saying I think it varies from state to state or country and the particular specialty facility. Also we did it almost three years ago so I'm sure prices have changed and probably gone up. I can totally relate to your concern about the price. We paid approximately $1,700. We used a specialty animal hospital that we had been to many times before with our dog and cats, therefore, trusted them implicitly. They use scintigraphy to determine the appropriate amount of radioactive iodine needed which I feel is imperative and are associated with a major university veterinary medical school. I'd also like to add that their staff was extremely helpful and attentive which was reassuring. They explained the procedure in detail prior to us committing to the I-131, answered all our questions, told us to call as many times as we wanted when he was in isolation there and kept us apprised of his demeanor. I knew they doted on him because one of the techs told me things about his demeanor that they would have only known if they were keeping a close eye on him. The radiologist talked to us when we picked him up and once again told us to call with any questions or concerns. Should you choose to go this route with the I-131 treatment I hope you have the same experience we did with Carleton. :lovecat2:

ETA: You may want to ask if the facility you choose accepts a payment plan since cost is a factor.
 

VinceL

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It has been many years since our cats had the I-131 treatment. I seem to recall it was around $800. It sounds like prices have gone up dramatically. :(

One thing to be aware of is that when you bring your cat home, he will be radioactive. You have to limit your close contact and definitely don't sleep with the cat. This was very challenging for us with Lexi because she normally slept up against me every night; I had to sleep in another bedroom with the door closed. She didn't get in bed with my wife.

You also will need to wear gloves when cleaning the litterbox and set the litter outside for awhile (I don't remember exactly how long it was) to allow the radioactivity to decay before putting it in the trash.
 

neely

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You also will need to wear gloves when cleaning the litterbox and set the litter outside for awhile (I don't remember exactly how long it was) to allow the radioactivity to decay before putting it in the trash.
Three weeks before you can throw your regular litter into the trash. However, there is a special alternative litter they gave us which is perfectly safe to flush down the toilet should you choose to use it called: sWheat Scoop We were also told to throw the pooper scooper out and use an inexpensive dustpan broom to sweep up litter on the floor which should also be thrown away.
 
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Draco

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I personally had Radioactive Iodine Treatment for my thyroid cancer 12 years ago. I know all about the isolation and how to properly dispose of certain things, no sharing and such- it was hard as heck. I had to board my cats since I lived in a small studio apartment and couldn't isolate myself from them nor did I have anyone to take care of them for me. I imagine the same process and procedures would be the same for the kitties.

I did some online searches and seems like the cost is between 1500-1700. Right now he's doing well on his medication, but if anything turns I will consider it then.
 
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