Have any of you who have taken Methimazole been on it while having elevated ALT/AST #s?

I'm wondering b/c my Endo has kept me on the Methimazole 30mg/day even though my ALT is elevated.

In early June, when I went to the ER with tachycardia and was diagnosed with hyperthyroidism, my ALT was 109 U/L (normal <32) and my AST was 48 U/L (normal <33). At the ER I was told this was related to my diagnosis. I was then put on Propranolol and was referred to an Endo.

As some of you know, I had an Endo, who wasn't really being helpful so I changed to a new one. This old Endo put me on Methimazole 30mg/day a week after my visit to the ER. At the time my ALT/AST were: ALT 76 IU/L (normal 0-40) and my AST 29 IU/L (normal 0-40). My bilirubin was 0.4 mg/dL (normal 0-1.2). The Dr. didn't think much of my elevated ALT and so I started the Methimazole.

I changed Endos and on July 9th my new Endo told me to continue taking the Methimazole 30mg/day even though at that time my ALT was 77 U/L (normal <32). He did not order AST, bilirubin.

The ALT was obviously elevated so my question is, have you been on Methimazole even though your liver #s were elevated and was your Dr. okay with it? My next set of labs is next week and I'm trying to get ready in case the #s are still elevated. He has ordered ALT only (plus TSH, FT4 and WBC).

Per Drugs.com, the Methimazole should be discontinued if hepatic transaminase values exceed 3 times the upper limit of normal. So, in my case I'm guessing it would be if the # is > 96, since <32 is the normal. This makes me feel better because last time my ALT, as I mentioned, was 77 but I would still like to hear from you and your experiences.

Thank you in advance
Caro

I would trust your doctor and just ask that your liver be monitored along with your thyroid. It sounds like you will get these numbers next week, so if methimazole is causing you any liver issues, you will know- so that is a good thing! In my case, my liver enzymes were normal before methimazole and 8 times the normal amount on just 5 mg. 7 weeks later. It was pretty clear what was causing the problem!

Since your enzymes are elevated, I would stay clear of Tylenol and alcohol. Take Advil (metabolized through the kidneys instead of the liver) if you need pain relief.

If methimazole does end up causing problems, I wouldn't switch to PTU as there is a 50% chance of having liver issues on PTU if you have them because of methimazole (I don't have the reference for this, but it is from a primary source, as after my issue with methimazole, I did a lot of research to see if trying PTU made sense- which it didn't.) My endo. was willing to let me try PTU, but he didn't recommend it. So, RAI or surgery were my choices. I opted for surgery.

Don't worry though; it's not likely that methimazole will cause you problems; I think it's only a 1% chance. Either way, you'll know soon. The liver regenerates quickly, so if there are problems, you should be fine once you stop the meds.

Alexis

Alexis,

Thank you for your response. I feel like I do trust him and therefore I'm still taking the Methimazole He was highly recommended but you know how it is, one worries and wishes/hopes for the best and well … having the elevated ALT scares me. I have met people who needed liver transplants in the past and I wouldn't want to be there, you know? …

8 times the normal in just 7 weeks … wow!! I'm on the 6th week right now, so next week when I get my labs will be the 7th. I'm hoping for the best.

As of right now, I've only taken Tylenol twice and only 500 mg. I haven't had any pain thank God but the other day I did get a headache and well, I went for it. The headache was starting to turn into a migraine. I hate migraines. I will follow your advice on the Advil. I don't drink alcohol so I'm good on that. You know, before I was diagnosed I was taking a lot of Tylenol. I was getting headaches all of the time. Probably all related to GD.

Yes, I don't want to try PTU. It scares me. I hope I'm not one of the 1% and that my ALT is either stable of lower.

I'm so glad your surgery went well and that as far as the surgery goes you are doing excellent. One less load off your shoulders, right?

Thanks again,
Caro