Test Results Interpretation

[jenne23]

Hi, My GP has said my results are stable/ok but when I checked my TSH it looked low. Serum free T4 is 19.9 and Serum TSH is 0.02.

Would be grateful for any insights as feeling generally fatigued.

[Buddy195 Administrator]

Welcome to the forum jenne23…. I see this is your first post 🦋

So we can offer better advice, can you tell us more about your thyroid condition, eg when you were diagnosed, ongoing symptoms, current medication & dosage, plus ranges for the TSH and FT4, as these can vary between laboratories. Was FT3 tested?

Plus any antibody and key vitamin tests (ferritin, folate, vitamins D and B12)

If your GP is unable to complete all the above (eg if TSH is within range, some surgeries may not be able to access FT4 and FT3 tests), you could look to do this privately, as many forum members do, for a better picture of your thyroid health:

thyroiduk.org/help-and-supp...

[SlowDragon Administrator]

Always test all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

how do you feel

Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine

For full Thyroid evaluation you need TSH, FT4 and FT3 tested

Also both TPO and TG thyroid antibodies tested at least once to see if your hypothyroidism is autoimmune

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

About 90% of primary hypothyroidism is autoimmune thyroid disease, usually diagnosed by high TPO and/or high TG thyroid antibodies

is your hypothyroidism autoimmune

[Hashihouseman]

potentially hazardous! - pubmed.ncbi.nlm.nih.gov/315...

[Poniesrfun in reply to Hashihouseman]

The subjects were not on thyroid replacement hormone. And there was no correlation with “in range” T3 and AF - important even though they only mentioned as a side note

On the cancer boards, physicians still frequently over-medicate with T4 to keep TSH low then prescribe beta blockers with no regard for T3. .A little differently than here, we tend to suggest lower FT4 levels with higher FT3 levels to suppress TSH without causing the “wired and tired” that can happen with high T4/low T3.

Patti in AZ

[FallingInReverse in reply to Poniesrfun]

Patti, thanks for that context, well read!

Hashihouseman Also wondering if you meant to post this somewhere else as it’s not relevant to the original poster.

[Hashihouseman in reply to FallingInReverse]

I meant to post it exactly where I did.

It is highly relevant to any circumstances of higher freeT4 because it provides evidence of the link between that and adverse cardiologies, whether the fT4 levels are endogenous or exogenous with iatrogenic consequences. Of course you are free to ignore data that isn't specifically founded on a very specific set of circumstances that would seem the only thing that could make the data relevant but the point is; the link with fT4 however caused. Of course there may be circumstances where higher risk levels of fT4 are the lesser of 2 evils but where there is scope to reduce them to statistically normal euthyroid levels (e.g. 14-15) then the evidence indicates the importance of considering this.

Moreover the paper I referred to literally states the evidence warrents a review of T4 treatment levels - specifically relevant. The fact there was no correlation with normal euthyroid levels of fT3 or even higher than normal levels and AF could indicate that there is a physiologically sensible route to reducing excess fT4 by adding exogenous T3 treatment to a lower dose of T4 to resolve hypothyroid symptoms. Just in case you still assert this is not relevant or even simply useful for some people I also refer to this paper (specific to total thyroid removal but containing directly relevant descriptions of the relationships and risks of high fT4 however caused). See Fig 2 in particular for the summary of why all this is significant and relevant. ncbi.nlm.nih.gov/pmc/articl...

[Hashihouseman in reply to Poniesrfun]

see my reply to fallingin reverse