Skip T3 dose when getting labs?

[ReneeC76]

Hi everyone, I'm curious about everyone's opinion on this. I'm on T3 only and will be getting labs drawn soon for my endo (FT3, FT4, TSH), probably will go in Fri morning. I've heard people say they skip their T3 dose the morning of the blood draw.

Does everyone feel that's the best route to take? Or do you feel it depends on when the last dose for the previous day was taken? My doses are 7am, 12pm, and 6pm. I'll probably go in for labs at 7am.

I'd appreciate any input, my wellness dr has opinions and I would just like to get as many opinions as possible to consider. Thanks.

[SeasideSusie Remembering]

ReneeC76

If I took T3 at those times, on the day before the test I would push my 6pm dose back to somewhere between 7pm and 11pm, that would then give the advised 8-12 hours gap between last dose of T3 and blood draw. On the day of the test take your 7am dose after the blood draw.

[ReneeC76 in reply to SeasideSusie]

Perfect, thank you for that. I wasn't sure what the appropriate time gap would be, I'm guessing we don't want T3 levels to be so low but yet not as high as they would be several hours after taking it? Thank you again.

[SeasideSusie Remembering in reply to ReneeC76]

Last year I had a thyroid test sprung on me without warning, I had taken my Levo plus T3 at my normal time that morning (it would have been somewhere around 4am-6am) and I said my results would come back high because of that. They sure did.

When I leave the advised time gap my FT3 result is usually around 5.7-6.2 (3.1-6.8), with that test where I'd taken my T3 before hand the result came back at 7.9 (3.5-6.5) - different ranges as it was a GP test and the others were private tests; however, it went from my usual 75%ish through range to 146%.

[ReneeC76 in reply to SeasideSusie]

Oh wow. That's good to know too. Since I'm taking a fairly small amount of T3 everyday, I definitely don't want my results to look high and have my endo freak out. She's been pretty good about listening to me and meeting my demands as far as this has gone so far. My fear was having my T3 be high out of range during the time of the labs and the endo thinking this T3 only situation is a bad idea based on that. Definitely going to do as advised and keep the 8 to 12 hour gap before the blood draw.