Night Before test

[lisan1]

Is it ok to take Ferrous fumarate with c vitamin the night before thyroid blood test? Or is it better to fast for 12 hours?

[SeasideSusie Remembering]

lisan1 There's no problem with taking your supplements the day before your thyroid test, just leave off the Levo for 24 hours.

You don't need to fast for 24 hours, you can't go with food for that long! Just have your evening meal the night before and then leave breakfast until after your blood draw, you can have water though.

[lisan1 in reply to SeasideSusie]

Oh, silly me! Of course I meant 12h fasting.

[SeasideSusie Remembering in reply to lisan1]

[humanbean]

I would avoid the iron pills the night before if I was you, not because it will affect thyroid blood tests (it won't as far as I know), but because it will affect any blood tests for iron or ferritin, in the event that your doctor does them.

A 24 hour break in taking your iron supplements before blood testing is always a good idea. If you know for certain, in advance, that you are going to have iron or ferritin testing done I would stop taking iron supplements for 5 days.