Taking synthroid morning of my Fasting Labs?

[hsmomof3]

Am I supposed to take my synthroid prior to going in for my fasting labs.  I take it in the mornings and my labs are scheduled for 8:30am.

Thank you
Debbie

[Mark Lupo, M.D.]

It should not effect the TSH - and would have small impact on T4 -- so ok to take med morning of labs.

[Lake Lover]

If you are having thyroid lab's drawn I would wait until after.  They say it doesn't matter but I have experienced an extremely low TSH the day I took my replacement and had thyroid lab's drawn.

[GravesLady]

I do.




GL
Hyper/Graves'/RAI

[GravesLady]

L-T4 (synthroid, levoxyl, etc) can be taken the same day. After all, the medication is accumulative.
"TSH testing is not influenced by the time of day the L-T4 dose is ingested".
However, Central hypothyroidism, the daily dose of L-T4 should be withheld on the day of testing.

Complete Summary  GUIDELINE TITLE Laboratory support for the diagnosis and monitoring of thyroid.  guideline.gov  (government)
National Academy of Clinical Biochemistry (NACB). NACB: laboratory support for the diagnosis and monitoring of thyroid disease. Washington (DC): National Academy of Clinical Biochemistry (NACB); 2002. 125 p. [495 references]

You can take your thyroid meds the same day and before test.

GL
Hyper/Graves'/RAI