Could I please have some help understanding my blood results? - especially FT3

Starting levo but decided before starting that I wanted to see what my FT3 was like and whilst I was at it to see if I had both thyroid antibodies. So had BH home blood tests.

Here are the results:

TOTAL THYROXINE(T4) 103 nmol/L (59 - 154 )


FREE THYROXINE 16.1 pmol/l (12.0 - 22.0 )

FREE T3 4.8 pmol/L (3.1 - 6.8)


Thyroglobulin Antibody *179.0 IU/mL ( 0-115)

Method used for Anti-Tg: Roche Modular

Thyroid Peroxidase Antibodies*184.3 IU/mL (0 - 34)

To compare with my previous results that have different ranges:


08/13 1.4 (0.35-5.5)

01/14 3.4 (0.35-5.5)

03/14 2.4 (0.35-5.5)


08/13 16.4 (10-19.8)

01/14 13.3 (10.19.8)

03/14 14.7 (10-19.8)


09/13 92(0-100)

01/14 247(0-100)

0/3/14 1229 (0-100)

So I now know I have both antibodies which is neither here nor there as I know now I am dealing with autoimmune disorder,

I know that my tsh is totally unreliable. From what has been explained to me with the different lab ranges I take it that a result of 3.78 with the range of 0.27 to 4.2 isn't the same as a range that my gp's lab uses (0.35-5.5) so had I had it done with my gp at the same time I would have had a different number...higher I expect. Should I just be disregarding TSH anyway because of the autoimmune problem which is obviously making it go up and down like a yo-yo eventhough still in range?

FT4 isn't super low but it would be better if it was higher.

Now FT3 is new to me and don't really understand it. Am I in right in assuming that low FT3 means conversion problem and what you are aiming for is a nice high FT3? Is mine ok? It's just under the half way point so does it mean I'm converting fine?

I also know that you are meant to do a ratio of some sort between FT4 and FT3, how do I do that?

4 Replies

  • Just to confirm - the BH results are BEFORE you started the levo...?

    Yes - generally, people need a FT3 towards the top end of the reference range.

    How much levo are you starting on..?



  • Hi louise,thanks for replying. That is correct, tests from midweek,started 25mcg levo this morning.

  • Thanks. :)

    Let us know how you get on! :)

    Are you taking it with water only, at least 30 mins to 1 hour before eating..? Just checking... :)



  • looks as though you are starting to get things under control....... that's gr8! the antibodies will take a bit longer

    to pipe down but looking good ....

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