How long do you hold biotin before a 50 mcg strip?
Stop biotin and biotin-containing supplements for at least 2 days prior to thyroid testing. Hair gummies count. Beauty blends count. High-dose neurologic biotin counts.
Some assays are hungrier. Ask the lab if they want a longer hold. The insert's floor is two days.
Can I keep biotin on workout days and only hold before labs?
The labelled hold is at least two days before the draw. Chronic high-dose biotin between draws still poisons the next vial if you forget the hold.
Energy drinks and bariatric blends can hide biotin. They do not replace a serum B12 and they do not belong next to a thyroid immunoassay.
What do you write on the requisition?
Biotin last dose, clock used, and brand or generic NDC. Those three lines turn a random TSH into a rating. lab-strip signal wants them on the slip.
If the lab uses a different assay than last time, write that too. Method changes can shift a number a little. Do not treat a tiny drift after a vendor change as a full 25 mcg event until someone checks.
The printout looks wild. Change 50 mcg tonight?
No. Ask the lab about biotin interference before you rewrite 50 mcg off one pair. Feeling fine with a 'Graves' printout while the gummies are open is a hold-and-repeat story.
A real over-replacement still has a pulse and a clinical exam. Too-much signs are symptoms, not a gummy.
How does biotin lie on the assay?
Biotin-streptavidin immunoassays can print a fake hyperthyroid or a fake hypothyroid picture. High-dose biotin can mimic Graves numbers with a quiet exam.
Do not start methimazole off a gummy artifact. Hold, redraw, then decide. List every wellness chew on the slip.
Is biotin an absorption problem like iron?
No. Iron binds the tablet in the gut. Biotin fools some lab methods. Fixing biotin does not replace the 4-hour mineral wall. The iron-and-soy scan is the gut job.
This page stays on the assay. Hold two days, redraw, then talk about 50 mcg.