Interesting T3 results- time for an increase an... - Thyroid UK

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Interesting T3 results- time for an increase and how to do so?


I’ve been on 100mcg T4 and 15 mcg of T3 (phased in over a few weeks) since mid May. My endo wanted bloods done before the first 6-8 weeks were up, which I did to satisfy him, and I have just repeated them quietly myself to get a better idea now that I’ve been on a stable dose for 8 weeks:


TSH 0.014 (0.27-4.2)

Free thyroxine 17.3 (12-22) 53% through range

Free T3 5.4 (3.1-6.8) 62% through range


TSH 0.029 (0.27-4.2)

Free thyroxine 15.7 (12-22) fallen to 37% through range

Free T3 4.94 (3.1-6.8) fallen to 50% through range

The results don’t surprise me as I can feel symptoms starting to creep back in (carpal tunnel, brain fog, low mood more often, difficulty sleeping, hot flushes, painful joints in fingers and knees).

Should I perhaps increase the T3 from 15mcg to 20mcg? I currently take T4 and 10mcg of T3 at 6am then 5mcg of T3 at 6pm. I tried splitting the dose into 3- what a pain with supplements, especially juggling getting enough iron!

My questions are-

1. Should I just add the extra 5mcg to the 6pm dose?

2. I know from on here that people can have a low T4 result when taking T3 but is mine (37% through range) too low? Is it ok to just increase T3 and see what happens?

Thank you so much in advance for reading and any advice gratefully received.

3 Replies

I think increasing the T3 dose by 5 mcg at 6pm, and waiting to see what happens, would be fine. You shouldn't increase both at the same time, so leave the T4 for now. That extra 5 mcg T3 might be all you need. :)

Kipsy in reply to greygoose

Thank you so much greygoose- really appreciate your advice. I will start tonight.

greygoose in reply to Kipsy

You're welcome. :)

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