How long should I go off iron supplements before testing?

Hi

I’ve been on 3 prescription iron supplements a day since January and am having my iron, ferritin, and cbc tested on Friday. How long should I go off my iron supplements to get an accurate reading?

Thanks so much

[SeasideSusie Remembering]

Pinkiris

Iron supplementation should be stopped for 7 days before any iron test.

Iron tests should be done after a 12 hour fast (water allowed) so early morning is the best time before breakfast.