Hi Everyone. I had a Thyroid Function Test this morning and I'm wondering why my TSH is so low despite FT4 not even being mid-range. My understanding, from this website, is that TSH should only be this low when FT4 is much higher, given that I'm on Levo only (no Liothyronine/T3).
>Latest Thyroid Function Test (Jun 2017):
Free T4: 14.4 pmol/L (11.00 - 22.60 pmol/L)
TSH: 0.06 mu/L (0.2 - 4.00 mu/L)
>Thyroid Function Test (Jan 2017):
Free T4: 14.9 pmol/L (11.00 - 22.60 pmol/L)
TSH: 0.02 mu/L (0.2 - 4.00 mu/L)
I was diagnosed in December 2016. Before Levo, TSH was 5.6, T4 10.8. I'm on 100mcg/day of Levo.
Any help, much appreciated.