Thyroid UK
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Advice with latest bloods and NDT dosing

Hi everyone, I posted on here a while back and found the advice given very useful so thought id give it another shot.

Im a 29 year old male who had a TT around 3 years ago. I spent around 1.5 years on Levothyroxine feeling crappy most of the time and lucky found a doctor who would prescribe NDT. For the most part i feel pretty good and can exercise on a regular basis but still have plenty of low energy days and i know there's room for improvement but im always scared to mess with my meds. After a recent blood test im thinking i might be a bit over medicated and my dr said i should maybe look into lowering my dose a bit (currently on 3 grains split in half am/pm) and wanted to see what people think. Last dose was at 4pm the day before and i had my bloods taken at 9:30 the next morning:

Free T4 - 12.1 pmol/l (range 12 - 22)

Free T3 - 6.3 pmol/l (range 3.1 - 6.8)

Iron - 15.7 umol/L

TIBC - 47 umol/L

Transferrin sat - 33%

Ferritin 119 ug/L

Active B12 - 101 pmol/L

Im starting to feel like a might be a bit over medicated- feeling a bit twitchy, occasional heart palps, but my free T4 is right at the bottom of the range and my T3 is pretty high and i wonder how my T3 is peaking during the day when i take my meds? Im wondering if i should i just try T4 only meds again or maybe i should try reducing NDT substantially and adding T4 or maybe just try and drop my current dose of NDT down to 2.5 grains? I know its really trial and error but its hard making these decisions and would be good to hear what people think.

Thanks for reading and i look forward to hearing your thoughts


5 Replies


FT4 is often very low in range when taking NDT and is sometimes below range. FT3 is within range so you aren't over medicated. If you *feel* over medicated after taking a dose it may be the T3 peaking. You could certainly reduce dose by 1/4 - 1/2 grain to see whether symptoms improve.

Ferritin is usually fine >100.

Active B12 >35 is unlikely to be deficient.


Why would you think that going back on Levo will give you different results to last time? Low T4 is normal with NDT, and really FT3 is the only relevant figure. You have enough to convert if you need to, and can.

I take my entire dose in the morning and feel fine, but if you feel you go over at times, I'd suggest you think about splitting the dose and/or taking some at night.


Hi there, thanks for your quick responses. Ruthi, i know it sounds so stupid to consider going back to only T4 but when i was taking levo before i had never considered other things like B12, Iron, Vit D. I now have them a lot more in check and wondered if i might feel better by trying to get my Ft4 higher in the range and see if im now better at converting. In reality i dont really think i want to give that a go because i truly believe in the efficacy of NDT and feel for someone who is young and has had a TT it is more sensible for my long term health to have more bio equivilanet hormones.

What do you think about lowering NDT maybe 1/2 grain and then adding a small amount of T4? Does any one have experience with this? Where do you feel best within the reference ranges?

Thanks again


This link may be helpful and click on the links in blue. Dr Lowe would only prescribe NDT or T3 only for resistant patients, and you may find his 'Safely Getting Well etc' helpful He wrote this for patients or anyone suffering. The only blood tests that were taken was for the initial diagnosis, thereafter it was all about how the patient 'felt'. He was also an Adviser to Thyroiduk before his untimely death.


I would cut. A K on the exercise a little. D see if that makes a difference you may be using up too much of your T3.


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