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Thyroid UK
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GP has tested TSH/T4/T3 all too low

Hello again Thyroid warriors. My GP has just checked my bloods, they know I am self-medicating with NDT, 3 grains a day. my results follow. I have no energy and struggle to get anything done, still. I have issues with DIO1 and DIO2 hence T3 conversion problems and numerous methlyation Snp's too, contributing to the energy issues. Can anyone comment on the thyroid results? Thank you :-)

free T3 level3 pmol/L range 3.5 - 6.5pmol/L

free T4 level9 pmol/L range 11 - 23pmol/L

TSH level0.21 mu/L range 0.35 - 5.5mu/L

Serum vitamin B12303 ng/L range 180 - 640ng/L

Serum folate8.7 ug/L range 3 - 20ug/L

Serum ferritin63 ug/L range 20 - 200ug/L

Serum cortisol325 nmol/L ( tested because of previous 767nmol/L 2 yrs ago)

9 Replies


You are undermedicated as both FT4 and FT3 are below range. It's not unusual for FT4 to be low or below range when taking NDT but FT3 will usually be between 5.0 - 6.5 when you are optimally dosed. TSH will very probably be suppressed <0.1.

The T3 in NDT should overcome poor conversion when you are optimally dosed.

B12 is low in range. If you have symptoms in b12deficiency.info/signs-an... go to healthunlocked.com/pasoc for advice.

Folate is okay.

Ferritin is optimal halfway through range. You can raise ferritin by supplementing iron with 1,000mg vitamin C to aid absorption and minimise constipation. Take iron 4 hours away from NDT.

1 like

Hi Clutter, yes, that makes sense. I did get hold of some t3 to add to my NDT but as I knew my GP was going to run tests I didn't take it. I'm not sure how I am going to handle the TSH result as she will see that as me being over-medicated :-( tell her one thing and do another I guess.

I hear you about the other results. These are long standing issues which I have all the supplements for but being post- menapausal, I have been holding off iron supplementation. Thanks for the info re splitting up the NDT and iron, didn't know that.

Thank you :-)



If your GP thinks that TSH 0.21 means you are overmedicated while FT4 and FT3 are below range she really doesn't know what she's doing.

Are you prescribed NDT or self medicating?


Hi Clutter, that made me laugh :-)

I have been self-medicating for the last 30 months. I haven't seen an endocrinologist since I was first diagnosed 9 years ago. I take thiroyd x 3. I just bought some cytomel 25mg and intend to take it very steady, half a tablet in the morning see how I go.



Why don't you increase Thiroyd dose instead of adding T3?

12.5mcg T3 is equivalent to half a grain of Thiroyd.


Just having a scroll down the list of possible symptoms of B12 deficiency and I have so many of them but the worst one is, I have had 2 bouts of DVT which went to my lungs in the last 18 months and am now on permanent blood thinners. The plot thickens.


NDT will suppress your TSH level but you likely know that already 😌. Have you tried going GF yet? Consider looking at adding selenium to your daily supplements too.



Hi Rusty64, yes, I take selenium every day. Had my Vit d tested a couple of years ago and it was just above 60 so I supplement that in the winter.

About 15 years ago I did the Carole Vorderman detox ( no alcohol, meat, dairy, gluten), lost a stone in a month and felt great after 2 weeks. I have tried it again more recently but my body didn't respond. I am working myself into the right position to have another go at really focusing on my needs.

thank you :-)


Thanks Clutter, that would up the t4 as well, I could give that a go instead.

I was just reading the B12 info, I definitely need to take my supplements again. I found out about 3 years ago that I had had consistently low b12, folate and ferritin for at least 8 years and had not received any treatment except an offer of ferrous sulphate which I declined and did my own thing. Having discovered my potential issues with methylation I have backed off the supplements a fair bit but started again yesterday :-) I have all the right ones for my genetic profile.


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