Update: Spice is on methimazole 5mg. So before they upped his dose he took 2.5 mg twice a day. Now he takes 2.5 mg in the morning and 5 mg at night total of 7.5 mg a day.

I just want to tell you my cat's experience with hyperthyroidism. My male cat, who was a pretty large kitty, was diagnosed with hyperthyroidism when he was about 14 years old. He was prescribed special food, one was Science Diet and the other was Purina. I forgot the exact food, as this was several years ago. He was also prescribed methimazole twice a day, but again I can't remember the amount. He continued to lose weight even though he was medicated and eating a special diet. He did not seem to like the food, and only seemed to eat enough to keep himself alive. After about 6 months, I noticed that he would run from me every time I walked into the room. I had to chase him down to give him his pills. It was breaking my heart that my big robust cat was wasting away in front of my eyes. It was also so troubling to realize that he had become afraid of me because I was giving him his medication. I had a heart to heart with my husband, and we decided that we would rather that he die of the hyperthyroidism, than to live frightened of me because of the medication.

I subsequently went to a specialty pet store and bought the highest quality food that I could find! He started to eat with gusto! It was so beautiful. He ate so much in the first few days that he started to fill out and gain weight!

The vets' office eventually called me because they noticed that I had not picked up his medication, and I told him that we were not going to medicate him anymore and I had changed his food to something that he actually wanted to eat! They told me that if he lived another 2-3 months, I would be lucky. They said that his values showed that he would wither away in a very short time. I responded that I would rather him wither away than to be afraid of me. He had always been my baby, and to see him scatter when he saw me was to much for me to handle. It had gotten so bad that he would not even let me pet him. He lived in constant fear of having a pill stuffed down his throat. (Before anyone criticizes the fact that I had to push the pill down his throat, I had already tried pill pockets, boiled chicken, hiding it in his food, and anything else that I could think of.)

Needless to say, he lived another 4 years, and ended we ended up having to put him down from complications that had absolutely nothing to do with hyperthyroidism!

My cat 19 also, was loosing weight and so on, was misdiagnosed with hyperthyroidism and ended up having cancer; but it took years (and lots of wasted $$$) before our vet could even diagnose her with it. Now I always suggest that when in doubt, go to see a vet that specializes in feline medicine or get a referral and go see a specialist. It was a specialist who finally diagnosed our girl correctly, but I wonder if we could have saved her or her quality of life wouldn't have been much better if I had known to go to a specialist at the first sign of trouble.

Jilldag, I'm glad your kitty was able to thrive without needing treatment for hyperthyroidism! Thank you for telling me about him. It gives me a little hope.

Spice is also a large cat in addition to having been rather obese throughout most of his life. We still affectionately call him "Fatty" even though he is now only 8 lbs (down from his personal record of 20 lbs). Eight pounds looks very, very skinny on him, even though it is within normal range for a domestic cat.

Thankfully, he doesn't mind being pilled. In fact, since starting treatment, he has regained more of his personality, which is a relief. He'd previously been in that hyperthyroidism haze I've read about. I do try to make pill time more enjoyable by giving him his wet food right after he gets his pill as well.

I am concerned that he doesn't like his food, but I'm not sure what I can do about it... he is on his special food for his kidney disease, not the hyperT. If his kidney levels remain normal, I might ask the vet if we can switch to something with more protein and see if that helps him gain weight. On the other side of things, if his kidney levels drop, we will probably have to start doing IV fluids at home.

I forgot to mention, after starting treatment, his voice got very horse. He'd meow and it seemed like he really had to make an effort to produce sound. Vet has no ideas what is causing that. Has anyone else experienced this with feline hyperthyroidism?

lukkiirish, how was your cat diagnosed? My vet ran a blood test and found the elevated thyroid hormone levels, which fell into normal range after treatment.

It is possible he has underlying cancer as well. He had a stroke or seizure (something neurological) in the spring of 2015, and we thought that was the end for sure. He couldn't stand up or walk or use the litter box on his own. I held him up to use it because he wouldn't go outside of it (good mister kitty). We had put puppy mess pads under him so it wouldn't have been a big deal. I usually had to clean him up afterwards anyway.

We took him to a specialist. They said it was probably a brain tumor and wanted to do an MRI, but he had an arrhythmia which would make anesthesia for the MRI risky. So they wanted to do a whole course of other tests to ensure his heart was strong enough for anesthesia, then do the MRI, which would only diagnose, not treat. It was unfortunately out of the question due to the cost. We took him home and made him as comfortable as possible. They told us to prepare for the worst. Within a week he was walking again and eating and drinking like normal and has recovered as best as could be expected until his drastic weight loss the past few months.

My main question really is if it is normal for cats to continue to lose weight after starting treatment for hyperthyroidism? If not, I'm sure it is an underlying problem potentially related to his possible brain tumor. I just wanted to know if I should start worrying yet.

Yes, they can. That was my point. The prescription food is not very tasty to some cats, so even though they are medicated and on a special diet, if they don't consume enough calories they will still lose weight. I found that my cat did very well on Weruva. There are many different flavors and my kitty loved almost all of them. He started eating more, so he started gaining weight!

I'm sorry Spice is having such a tough time. I know it was years ago but I wonder just how elevated his kidney levels were when you started him on the prescription food. I ask because I've had pets that had higher than normal levels but it was normal for them and they lived long healthy lives and died from other complications.

If you want another opinion I would seek out a vet that specializes only in cats and iI would also do as Jilldag and introduce a canned cat food that he will eat. If he's feeling bad, then he's even more unlikely to eat the prescription food and keeping weight on him is more important (IMO) than following a prescription diet. Has he been checked for diabetes?

The high white cell count is concerning and since he's appears to continue to lose weight, I wouldn't wait until Sat. to have him checked.

I assume you've read this?

In case somebody has troubles with the pills -Methimazole is also available in a Quickdose pen as a transdermal med. Easiest way I have administered a daily dose of medication.

One of our cats has a fairly new diagnosis and we started out with 2.5 mg twice a day. Her thyroid numbers went way down on it but her kidney values crept up. We are now on 2.5 mg once a day and I'll have her tested again in the next couple of weeks to see where we are.

jilldag, I agree he needs to be on a food that he will enjoy eating enough to gain some weight. I am hesitant to take him off of his kidney food until I know how the higher dose of the hyperthyroid is affecting his kidney levels. I will talk to the vet when I see him this weekend. I am also planning to see if there are any supplements available to help cats gain weight. Thank you again :)

annztoo, yes I have scoured the internet for information on feline hyperthyroidism, but thank you :) Depending on the results of his recheck this weekend, our vet may recommend a specialist to look into potential underlying causes of his continued weight loss. I think he'll be okay until Saturday. He is eating and drinking and acting normal. They want to wait three weeks to recheck his levels again anyway, and Saturday is exactly 3 weeks from his last appointment. As I understand it (could be wrong), the problem with normal cat food is that is it high in protein to mimic a cats natural diet, and cats with kidney problems have trouble digesting protein which further decreases the function of their kidneys. I will talk with the vet this weekend after seeing his kidney level results on the new dose of Methimazole.

glaserberl, do you know if the quick dose pen costs much more (or less?) than the pills? Right now Spice's prescription is about $20 a month. How has your kitty's weight been affected since treatment?

glaserberl, never mind, i just saw you put a link to it. Thank you!

Cats I've had with hyperthyroidism gained weight after treatment was started.

Encourage you to get a second opinion, from a feline specialty vet, just to help make sure nothing is being missed. Second opinions are often very useful.

yes over a course of time our vet did bloodwork numerous times. She swore it was the thyroid and referred us to the specialist to have it removed. The minute he saw the bloodwork and heard what her symptoms he disagreed. he did a simple ultrasound and found cancer in her abdomen. She was spoiled rotten and we miss her every day

CKD cats are tricky; kidneys not flushing out toxins as they're supposed to do means that they recirculate through the body in the blood. These cats (and dogs, humans, etc.) often enter the vicious cycle of feeling nauseous, not eating, and therefore losing weight. High protein diets are very appealing to many cats, but contraindicated in CKD (because high protein is more strenuous on the kidneys to filter), so encouraging them to eat the less appealing kidney diets can be tricky. Semi-weekly subcutaneous fluids can be helpful in supporting the kidneys when they begin failing, but remember that it's only palliative care. Hopefully you can find a good balance for your little guy. Please don't misinterpret this, as I don't mean it to be morbid or rude, but keep in mind that he is 19 years old and that is beyond the normal lifespan of a typical house cat. It's only natural that organs begin failing, but it's less about age and more about quality of life. I've seen many heartbreaking cases of clients delaying euthanasia and the pet ends up practically starving to death :(

lovekcdillas, I never expected him to stick around this long, so no worries. He was always pretty obese and no matter what diet or exercise regimen we tried, he maintained his chubbiness. So this made us worry that he'd have complications that would shorten his life. He does have arthritis and no longer jumps up (he can jump down), but as far as weight related complications, I think that's the extent of it. So we got very lucky with him.

When he was last checked at the vet, his kidney levels had remained in the acceptable range. I do not know what they were when they were elevated. The first time we noticed the elevation, we were there for his neurological episode (I described it in a comment above), and the blood test was checking for diabetes. The vet just mentioned his kidney levels were slightly elevated, and if he made it through what we now believe was a stroke, we should start him on the prescription kidney diet.

This weekend when the vet sees him, I'm going to talk to him about adding a little more protein in, given his kidneys are doing ok.

Do you think it would be an acceptable treatment to add more protein into his diet in order for him to gain weight back and support his kidneys with subcutaneous fluids in place of the low protein diet?

We had a kitty who was on subcutaneous fluids twice a day towards the end. Once a week would not be too difficult to keep up with after that experience.

As of right now, he is eating enthusiastically and walking around, interacting with us and the other pets. He snoozes on cozy blankets and in sun patches. He likes attention and sitting with us on the couch. Loves being brushed. Still bathes as best as he can manage. I do not think he is ready to go yet, but I am prepared to recognize the signs when he starts showing them.

I'm glad for you that he still seems to be enjoying life :) the hardest part about having pets is having to outlive them; they really are such a wonderful addition (I think necessity!) to our lives. I'd leave it to the discretion of your vet to decide whether adding a more palatable protein (like baby food) would be ok for his CKD. As I said, it's a vicious cycle, so while adding something really yummy in may make him more inclined to eat, it may end up being a strain on his kidneys and just continue the progression. Depending on what his kidney values are on the blood work (and assuming his heart is in good health), subcutaneous fluids shouldn't hurt; if his values are only mildly elevated, your vet may not even see it as necessary at this point in time. There is also a drug called mirtazapine that is used as an appetite stimulant that's usually given every 3 days or so as needed; you could ask your vet about trying that (but it's not really a long term solution).

Hi Shannon, I know the original post was 3 years ago but I was wondering how is your cat. my Cat Luna who is 15 is loosing weight too.

Today is Nov. 16, 2021 - so obviously this post is meant for Dudette (and anyone else who has a hyperthyroid cat). We have a 15 year old cat who was recently diagnosed with hyperthyroidism. He also is on 2.5 mg of Methimazole twice a day. He did gain 1.5 lbs. as per his recent blood test (he has had 2 tests over a three week period) with a third test being set for the end of Jan. unless we notice something else is wrong. I wish he could be pilled, but there is no way. We are in Canada so the Methimazole must be custom compounded - we give it by ear in transdermal form. I know all about custom compounding due to a thyroid issue with our previous pet so know about the lead time when ordering and the importance of checking the expiry dates. He is not on the Hill's y/d because we have another cat who is not hyperthyroid. I also doubt either of them would eat the Hill's y/d because so far, despite spending a fortune on every type of wet cat food out there - plus trying to cook for them, they only like the one type of food - and it is available only at the vet's as well. But at least it comes in 3 oz. cans. I think that the thyroid food comes in 5.5 oz. cans? The kitties like fresh food so it is hard. I have resorted to putting the cans with lids into hot water and waiting 15 minutes but they seem to know. I dread the day that the food is not available or is reformulated. It is doubly hard with the wet food and a lot goes out to the street. Then we have the shortages and in Canada it is even worse than in the U.S. since so many of our products come from the states.

Re a second opinion, depending on where you are I would line up the new vet first. We have an awful problem in Canada and I know it is also bad in some states. Our vets are operating via a closed door policy meaning you drop your pet off at the door wearing a mask and wait. I absolutely do not want to go to an ER should the need arise because people have waited as long as 15 hours - and again, a closed door policy. It is suggested that you call first to even see if they can see your pet. So just be careful! And of course it is very cold here in Ontario.

Looks like many cat specialty vets in Ontario, good luck!

@Dudette Tenorio, where are you located?

Hi there! I'm in Tijuana, México. Luckily the border has opened, and I've gotten my covid shots, so I will look for another opinion in San Diego.

So Sophie is practically skin and bones now. She has a vet appointment this Saturday at 9:30. I found yesterday an article mentioning that geriatric, hyperthyroid cats may suffer from cachexia and/or sarcopenia, which are terms to describe the wasting of muscle and fat, it mentioned that capromorelin has improved the condition in cats, so I'm going to ask my vet about it, see if she knows anything about the treatment. She is a really great vet. She is the hyperthyroid specialist in Tijuana, but a fresh pair of eyes is needed.

Sophie is not down though, she is playing and loving, and doing zoomies. I'm feeding everything and anything she seems interested in. She likes fancy feast as wet food and she still eats some of her dry Hills y/d food. She does waste a ton of food. I warm her wet food in the microwave, 10 seconds at a time, she seems confused and kind of growls when going "niom, niom, niom". :)

I'm worried and sad, but I also don't want to overwhelm her. The reality is that she has gifted me 17 amazing and wonderful years, full of happy memories. What more can I ask? And Thank you for your comments and help. I'll keep you updated.

This is Sophie at my workplace (August, 2021). I used to bring her with me to work, but we moved and wasn't allowed anymore.

Cute Sophie! Always wanted a job where I could bring kitty to work.

Looks like San Diego has a feline only practice. In general, I prefer feline-only vets. (Disclaimer, I don't know Dr. Middleton.)

Good luck.🐾🐾

Dudette, our 15 year old hyperthyroid cat was on Cyproheptadine 20 mg (again transdermal) for a few weeks and then his appetite greatly improved so we were told to stop using it and just give our cat his transdermal Methimazole (or Meth) as I call it. So far so good. We just have to watch the expiry dates on the custom compounded Meth. We also have a bottle of Rebound, also a cat appetite stimulant which we have not used as yet.

He is also on a dose of Vitamin K daily (this time liquid which can be added to food or given by syringe but in the mouth. We have the beef flavour.

I know that eventually his kidneys will be affected.

Please advise how your kitty does with the Cat vet.

Hi fellow cat parents, it's with a void in my heart I let you know that my beautiful baby-girl Sophie, passed this past January 8th, at 8:30 a.m. She went peacefully, with love, treats and incredible stoicism. She was a lady since she was born until her last moments. My Universe is that much dim.

Im so so sorry to hear of your great loss of beautiful Sophie. 😞 I’m sending u huge virtual hugs!! I’m dreading this day with my beloved Romeo, who is about to be 20, has hyperthyroidism & kidney disease. It doesn’t matter how old they are, it is still extremely painful & a tremendous loss. 😢