tapazole side effects

Hi,

I searched some old posts on TCS to read about other's experiences with hyperthyroidism and medication. My kitty, CC, was put on 2.5mg of Tapazole/twice a day (brand name for the drug methimazole, I think). She just started her third week on the drug, and she was throwing up all day two days ago. She seems better, but she did throw up this morning. I was giving her the meds crushed up in a little tuna, and I stopped that because I was afraid that was causing the vomiting.

So, I guess I have two questions/concerns:
1) To isolate what might be wrong, can I take her off of the tapazole for a few days safely?
2) I called my vet to ask about side effects, and she said CC would have exhibited vomiting almost immediately after taking the first pill if that was the issue. This is the opposite of the research I've conducted online.

Thank you all in advance! I've learned so much from reading the posts on this site.

Vets aren't always up-to-date when it come to hyperthyroidism, unfortunately. It's quite possible that the vomiting is a reaction to methimazole--my mom's cat experienced that along with spikes in her liver values and ended up unable to take it at all due to the effect on her liver. I would talk to the vet and explain your kitty's symptoms, and then suggest taking her off methimazole and restarting it at a lower dose in a week to see if she's able to tolerate it in smaller amounts. You can also try the transdermal form of the medication; since it bypasses the digestive tract, sometimes it causes fewer gastrointestinal side effects.

If your vet balks at stopping the dose or still says the side effects would have happened immediately, suggest that she go on VIN. The article below is from VIN but aimed at pet owners, so I'm sure there is information on VIN that discusses the time-range for side effects:

http://www.veterinarypartner.com/Con...=2&SourceID=42

This one is from another vet:

http://www.vetinfo4cats.com/catmed.h...7;20and%20cats

Yes, cats can have reactions to methimazole/ I would recommend the trans dermal type as well. cats seem to tolerate it better. Make sure it s good compounding pharmacy.

Oh, what would I do without this community? Thanks to both of you for your advice. Can you please explain what I should be asking about? I'm not sure what transdermal medication is...

Thank you!

They can compound it into a gel and you can rub it on the cats ears where it gets absorbed.

Oh, sure. I should have picked up on the "dermal" to mean something about the skin. I will definitely press for this from my vet. Thanks again!