Anyone with a hyperthyroid cat on methimazole?

Simone just started on this med, in her ear.

She has only had 3 doses, but today she is sleeping a ridiculously long time, like it's 2:30 now and she has been sleeping since right after she ate breakfast, about 9am.

Just wondering if anyone else noticed this as a side effect?

Thanks.

I won't use that drug anymore except short term.  I don't know many cats who lived much beyond a year after taking it.  The best results have always been the radioactive iodine treatment.  Expensive, a great call if the cat is young.  Read this article by a vet, very thorough.

http://www.allfelinehospital.com/hyperthyroidism.pml

Same drug is used in humans and common side effects include: 

Less serious side effects may include:

• headache, drowsiness, dizziness;
• mild nausea, vomiting, or stomach upset;
• itching, minor skin rash;
• muscle, joint, or nerve pain;
• swelling; or.
• hair loss.

Side Effects of Tapazole (Methimazole) Drug Center - RxList

www.rxlist.com/tapazole-side-effects-drug-center.htmRxList

I have a cat that has been on it for three years...she's 19.  I have noticed occasional vomiting.  She sleeps a lot but I attribute that to her age.  Normally, with all medications, they need to take it for a time for some side effects to subside.

I considered the radioactive iodine treatment, however, it is difficult to do with a lap cat.  The have to remain so many feet away from you for a time after returning home due to radioactivity.

I read that the cat must stay at the hospital for 1-2 weeks due to the radioactive iodine.

That was a turn off for me, I believe it would be extremely hard on her at this age. 

It's not out of the question but thought we would see how this goes for a bit at least.

My dad's cat just started her meds for hyperthyroid also. She's taking half a pill twice a day, not the topical version. We haven't noticed any increase in her sleeping. But she's 20+ years old & sleeps all day already! She's been on it 2 weeks & we have definitely seen an improvement. She isn't as ravenously hungry & seems to be putting on a little weight too. Considering her age & disposition, doing the iodine didn't seem like a great fit for us also. 

My cat was on methimazole for about 3.5 years, but pill form not transdermal. She did ok for most of that time and I was able to dose her with pill pockets for much of that time.

You do have to keep up with thyroid level checks though. Having the thyroid level get too out of whack makes for heart trouble and/or kidney trouble or other issues later. (My cat later had congestive heart failure as well as CKD.) You want to recheck at least every 6 months and some do more often if you can afford it.

Given the cost of all the meds and rechecks and the potential for better outcomes, I would absolutely do the radioiodine if I had it to do over again. Amber was 13 when diagnosed but lived to 17 and it would have been easier through those years and cost about the same, and maybe she would have lived longer! The hospital hold time is down to 3 days now. Normally you stabilize thyroid levels with the meds first if possible, so that still makes sense, but you may want to check out the radioiodine treatment at least if it doesn't require a many hours journey for you, and maybe even if it does. As the article linked above notes, the suitability or choice may depend upon how progressed the hyperthyroid was before brought under control.

Thanks everyone for the insight! It helps to hear other's experiences.

Great to hear the hospital hold time is down to 3 days.  I do know they do a trial first with the methimazole to make sure that getting the thyroid low doesn't cause side effects related to lower blood pressure etc.  My friend had to do that with his cat.  She was still fine when the level was normal so they did the iodine and now she has to be on thyroid replacement hormone the rest of her life.  I think she was 15 when she got the iodine done and she's 18 now, still fine.

Yes, 3 days makes it much more possible to me.

Your friend was one of the unfortunate ones then, they took too much thyroid out

One of the benefits is to eliminate the daily med.

Glad he is doing good though

Pill is no problem for me.  I just dissolve it in water in a syringe (no needle)  and shoot it down her throat.  She barely notices anymore.

Simone has been on transdermal methamizole for 10 days now, however 2 days ago she didn't get any.

I have no idea how this effects her, I don't imagine she has any built up yet, if it even does build up.

She is either playing a game with me, or just doesn't like me messing with her ears, because she will watch for me to get close enough to snatch her up for med time, and jet far under the bed where I can't get to her.

However the following day when she missed both doses, she vomited up breakfast and has had diarrhea for days now.

Not sure but think it is the hyperthyroid that causes it, so I feel like I am not doing a good job with this, and need to get creative with getting her doses each and every time so she doesn't miss anymore.

Is the meth supposed to help stop the diarrhea/vomiting?

Not worth the radiation treatment if it's old, but definitely do it if he's young! My cat had hyperthyroidism (or whatever the one is where they eat heaps). She died last year, but she was was on the tablet treatment for years and was fine. It wasn't fun tabletting her but it was worth it.

I had a hyperthyroid cat who was diagnosed at 7 years old. Giving her pills everyday was traumatic for her so I opted for the I-131 treatment. This was 7 years ago and I took her to radiocat in Baltimore, MD. She was kept there for 3 days and when she came home I just had to use special litter and not let her sleep with me for a week. She also had an enlarged heart due to the hyperthyroidism and it actually went back to normal after treatment. She had no complications from the treatment (which is rare anyway). I highly recommend it to anyone that can afford it and I would do it again in a heartbeat if any of my other cats were diagnosed with it. I-131 is a cure and methimazole just masks the symptoms.

Simone is at least 13 and could be older.

She also has moderate CKD. 

The diarrhea/vomiting is unusual to me.  Amber never had that on methimazole nor at any time when the main problem was hyperthyroid.  Now CKD, that caused some vomiting but she had the obvious CKD-type stomach upset symptoms like vomiting clear foam and such (which we treated with Pepcid and similar.)  I don't recall Amber ever having diarrhea during all the hyperthyroid and CKD years of her life.  So at the very least it was inconsistent and not an ongoing issue for her.  Of course that doesn't necessarily mean anything; apparently diarrhea and vomiting are cited as being symptoms in some hyperthyroid cats.

But given that it sounds like it started AFTER Simone started taking the methimazole, I wonder if it could be an indication that she isn't tolerating it well? A small minority of cats really don't tolerate methimazole too well as I understand it and can have serious side effects.  It might be good check back with the vet and let them know these symptoms and that they appear to be new after starting the methimazole, and see what they say. (If indeed that is the case.)

Hey everyone,

So Simone has been on the methamizole transdermal for exactly a month now, and has been getting her doses regularly, she has adapted to me messing with her ears and doesn't hide around that time anymore.

However, 2 days ago after talking with her vet, we decided she needs to decrease her dosage to 0.2 ml twice a day rather than at 0.5 mls.

She has had a decrease in appetite, below what her normal was prior to her increase before treatment started.

She was behaving depressed, disinterested, sleeping all day in odd places she never had before.

She continues to have diarrhea too.

I can't seem to find anything about the diarrhea, whether it's a sign of too much meth, or too little, or something else?

She does need to go have bloodwork done again, but since the change in dosage, we have to hold off now to see where her levels are with getting the smaller doses.

So she goes on the 3rd.

Feeling very concerned here..........

It just hit me tonight, I bet the methamizole has now unmasked how much kidney loss she actually does have.

When we did her blood prior to her getting on the med, vet said she is hyperthyroid and has moderate ckd.

Now I wonder what's it going to show now.

Diarrhea is over, suddenly..........

I feel like I'm not even being realistic, am I going to lose her soon?

Or can she get her dosage straightened out and come around again?

She's looking thin again

My friend got the iodine treatment for his cat when she was 13 and she's 17 now with no problems.  They first did the methimazole to bring down the thyroid levels so the blood pressure would drop and that would reveal whether the kidneys could function with the lower blood pressure (sometimes they can't) and hers were fine so they did the iodin.  It's no longer a 2 wee stay away.  His cat is doing great.  His wife's cat lived to be 23 or 24.

That is definitely not out of the question, I know when we go back on the 3rd and look at her blood results we will discuss where from here.

Like I was saying though, I have a suspicion that the meth is now revealing what is really going on with her kidneys.

She's not herself. Not at all, eating less, looking thin, hanging and sleeping in odd places, very quiet and non interacting.

It's making me pretty upset. I can't stand the thought...

My 13 year old girl Bella has been diagnosed with hyperthroidism and is in her 2nd week of 1/2 tab of methimazole;.  She's always been a picky eater but  now has lost interest in both canned and dry food and she has lost 2.5 lbs.  I'm trying to find out more about the radioactive route as it is killing both of us to pill her.

I live in Walnut Creek CA, in the Bay Area.  Has anyone found a vet that does the radioactive treatment?  My vet didn't seen interested in having me explore it.  I would appreciate any information.  I would also appreciate any advice on food. I have always free fed her on Taste of the Wild Kibble and Wellness Tuna pouch. She gave up on the Wellness and I've been trying regular tuna and tuna juice (she is a juice / gravy girl) mixed with KitKat or Weruva canned chicken but nothing interests her.  The only thing she consistently loves is the shaved bonita flakes and freeze dried chicken bits.

Being a senior on small income also makes it a challenge to do the best for her....but I will find a way to do what will give her a longer healthy life if I could just figure it out.

I would be very grateful for any thoughts, ideas, experiences.