Are you on NDT? - Blood test query: So I am on... - Thyroid UK

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Are you on NDT? - Blood test query


So I am on 2 grains of Erfa Thyroid, which I take first thing in the morning. I have bought a Medichecks thyroid testing kit. Does anyone know if splitting my dose the day before the blood draw will be okay to provide a reliable result? I have heard the last dose of NDT should be taken 8 hours before the draw, not 24 hours as with Levo.

5 Replies

8-12 hours AiryFairie

Thank you for confirming this.

Most of us in the USA split the NDT dose (E.g.. 6:30 AM and3:3 PM). 8 hours after the AM dose, before the PM dose, is sufficient time to do the blood work. If you wait too long then the FT3 level will be lower. If you go to soon after AM dose the FT3 level will be too high. I have experimented with this. When i did BW 12 - 24 hours before taking my PM dose, the FT3 was too low (endo would want to increase my dose and that would be too much). Half life of T3 is approx. 4 hours.

Thank you Celestialbeing , I will split the dose the day before. I have always taken NDT in one go, first thing in the morning - I don't trust myself to remember an afternoon dose as well!

I put an alert in my calendar on my phone. I have it set to 3:15 and a 2nd reminder at 3:30. I have it set so that the banner appears as well as a sound. This way, if my phone ringer is off, i will still see the banner reminder.

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