Thyroid UK

Blood results advice please


I have been on Levothyroxine for many years after having radioactive iodine treatment. My current dose is 125mg per day. I have just got results of latest blood test which I requested as I’ve been feeling so exhausted plus other symptoms (dry skin, trouble sleeping, muscle pain, bad nails, etc) I felt sure it must be a result of under medication. He ran a plethora of bloods but neglected to include FT4 I know my health trust won’t measure for FT3. So the results I have, which may be relevant to the thyroid are

Serum TSH level 0.71 U/ml (0.38 - 5.33)

Ferritin 34 ug/L (30 - 300)

The following were the only things out of range

Serum inorganic phosphate level - above range, 1.51 (0.8 - 1.4)

Serum creatinine level - below range 59 umol/L (62 - 124)

GP has marked the results as No Further Action. I am debating whether to make a follow up appointment with him or not. As my TSH is under 1 I’m thinking maybe it’s not the thyroid. I’d be really interested to hear what others think.


9 Replies

You can't possibly know whether your thyroid meds are right unless you have FT4 and FT3 tested. You can get them done privately with a fingerprick test with Medichecks or Blue Horizon.

Your ferritin level is dire and will be causing symptoms. It needs to be at least 70 for thyroid hormone to work. As it is barely in range I would ask your GP to do an iron panel and full blood count to see if you have iron deficiency anaemia.

I would also ask for Vit D, B12 and Folate to be tested as your ferritin is so low, one deficiency means that there could be others. Muscle pain could be low Vit D.


It could easily be your thyroid. Just testing TSH on Levothyroxine tells virtually nothing

For full evaluation you ideally need TSH, FT4, FT3, TT4, TPO and TG antibodies, plus vitamin D, folate, ferritin and B12 tested

See if you can get full thyroid and vitamin testing from GP. Unlikely to get FT3

Private tests are available

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.

All thyroid tests should be done as early as possible in morning and fasting and don't take Levo in the 24 hours prior to test, delay and take straight after. This gives highest TSH, lowest FT4 and most consistent results

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.

In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l.

Most patients will feel well in that circumstance. But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."

You can obtain a copy of the articles from Thyroid UK email print it and highlight question 6 to show your doctor

please email Dionne:

Professor Toft recent article saying, T3 may be necessary for many. Note especially his comments about current inadequate treatment for patients who have had RAI or thyroidectomy

Post with results after Thyroidectomy - low TSH and falling FT3


What an excellent paper written by AD Toft.

He states all of the things that I have been saying for many years to medical professionals, which sadly has always fallen on deaf ears, I assume because they think we can't possibly know what we are talking about, and anyway the cost of proper treatment they feel is prohibitive.

Everyone should be entitled to good health via the correct treatment. This forum shows there is much disquiet and suffering out there, largely I believe, to undermedication of T4 and the use of ablation therapies which should be reserved for cancer patients only.

Thank you for bringing this paper to the forum. I would urge everyone to read it and to write to AD Toft with their experiences, this might then help add sway to the need for more research into this debilitating disease.

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Thank you for the replies, looks like I’ll be going back for further blood tests.

I don’t know why they didn’t test T4 they normally do, previous results have been

Feb 2017 T4 14 pool/L (5.6-21). TSH 2.83 U/mL (0.38 - 5.33) Suggests euthyroid

Sept 2017 T4 19 (5.6 - 21) 0.64 U/mL (0.38 - 5.33) Suggests euthyroid

I will go back and ask for full thyroid screen (but have been told before that Tpo Isn’t relevant as I have no thyroid functioning thyroid gland?

I did have a fasting Anit-tissue transglutaminase level test last March the result was 0.4 it/mL (0.0 - 4.0). I’m ashamed to say I don’t even know what on Earth this is.

Thanks again for your help.


Your September results are very good BUT you'd need a free T3 test to see if you are converting T4 to T3 well enough.

You can find out from Google what anything you don't understand means

I have no idea what your results means and won't guess in case I am wrong.


Thanks again for the help.



TPO is relevant even with no thyroid gland as it shows you are still experiencing autoimmune issues

Anit-tissue transglutaminase is a coeliac test

So your medics are aware of this

Result was negative as it was in range

But very, very many with autoimmune thyroid disease have non coeliac gluten sensitivity (NCGS) and therefore you may well find a strictly gluten free diet helps


Thank you, that’s really interesting, I do have another autoimmune condition called Relapsing Polychondritis, it’s not very common, not many people (including GP’s) have ever heard of it. However, I’ve heard about gluten free helping this too. I’m going to look into it and see if that can help me to feel better.

Thanks again.

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Susan Blum suggests in her book "The Immune System Recovery Plan" that all autoimmune disease may be triggered or perpetuated by gluten and/or dairy intolerance

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