Low T4 Normal TSH

[carencat]

I have had graves disease for 4 yrs. I went from hyper to hypo. Now my TSH is normal and my T4 is low.
What does this exactly mean?  If I increase the meds my tsh levels go up.

any advice?

I see the endo in july
Thanks

[Mark Lupo, M.D.]

Would usually decrease the methimazole dose at this point as the TSH is bordering on the high side and the T4 is clearly low.  Your mild hypothyroidism is only due to the effect of the methimazole (a medication that lowers thyroid hormone production), so the dose needs to decrease.

[carencat]

Thank you for sharing your information. You set my mind at ease. This was twice my t4 was low I thought my pituitary gland was failing.

Thanks again

Carencat

[GravesLady]

Thanks for the information in which should help Dr. Lupo.

I don't know much about ATD dosing, but I am assuming it works the same as T4 brands (levoxyl, etc).  With T4 brands, dose would  be raised to lower the TSH.  By lowering the TSH will (normally should) raise the FT-4. So present dose might not be correct.

Hang in there, Dr Lupo will respond to your question in time.

While you wait, I am open for you, if I can be of help.

[carencat]

tsh 3.06     normal ranges    0.32-5.6
free t4  0.48     normal is   0.58-1.64

methimazole  10 mg

thanks

[GravesLady]

It would help to know your exact TSH and FT-4 level, with your Labs reference range and what type of thyroid medication you are on, and, the dosage.