Hi there, I had a full thyroidectomy in summer 2018 (follicular and papillary cancer found), radioactive iodine at the end of last year and have been for a scan and blood tests (post Thyrogen injections) a couple of weeks ago. Thankfully all seems fine but I’m curious about the results of the thyroid function tests.
The letter I’ve received post-consultation says Free T4 measured 22.5 (no reference range given but a google trawl suggests this is quite high) and TSH 0.06 (target 0.3-2.0). I’m on 125mcg Levo and have been for nearly a year and, apart from sometimes feeling a bit warm and putting on a stone in weight, I’m feeling fine. The consultant wasn’t keen on increasing my levo as she talked about the risk of osteoporosis vs the weight bit.
Could someone interpret those results for me, particularly as the TSH seems much lower than the bottom target? I’m aware I should know more than this being over a year into taking the meds but, because I’ve tolerated it well, I’ve never researched it!
Many thanks,
V x
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Cronkes76
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For full Thyroid evaluation you need TSH, FT4 and FT3 tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common, when only on Levothyroxine
Ask GP to test vitamin levels
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .
Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
Is this how you do your tests?
Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or all vitamins
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 special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random
Every lab has different ranges, so you would need range on that FT4 result
Thanks both, I’ve only been tested as part of the appointments (various times of the day) and was under a private endocrinologist until I had my thyroid ops so the more extensive testing was before being on levo.
I will follow up with my GP and see what they will do (I’ve had low ferritin before so that wouldn’t be a surprise but never had vitamins checked). May well follow the private route to avoid a wrangle! Very helpful thank you!
Good advice from Slowdragon. You really must have FT3 tested along with the other blood tests you've provided, especially as your TSH is suppressed. I think it's appalling that FT3 is not tested as a matter of course. It's the FT3 level in conjunction with the other readings that will inform you on how your body is utilising thyroid hormone and how to adjust your levothyroxine dose.
I have refused to adjust my dose without an FT3 reading in the past.
Most ranges of T4 have a top end of around 22 and your TSH needs to be kept low and suppressed because you have had thyroid cancer and require no further stimulation, or activity or encouragement of mutation within your body.
A fully functioning working thyroid would be supporting you with approximately 100 T4 + 10 T3 daily. I just think it makes sense to replace like, with like, and that both these vital hormones be on a patients prescription for if, and maybe when needed.
Some people can get by on T4 - Levothyroxine alone, some people at some point in time simply stop converting the T4 into T3 and some people simply need both these essential hormones dosed and monitored independently to bring them into balance and to a level of wellness acceptable to the patient.
Levothyroxine, T4, is a prohormone and your body needs to convert this into T3 which is he active hormone that the body runs on. T3 is said to be approximately 3-4 times more powerful than T4. So, you will see that " loosing your thyroid " and loosing just this little bit of T3 can influence your well being. I read most healthy people use about 50 T3 daily, so effectively you have ben down regulated by 20% of your overall T3 production.
Your ability to convert your T4 into T3 can be compromised if your vitamins and minerals are not optimal within the ranges, this is especially true of ferritin, folate, B12 and vitamin D.
So, to fully answer your post a full thyroid panel as previously suggested is a good idea, so we can then see where your T3 is in relation to your T4 - most people feeling well on a ratio of T3 to T4 of between 1/3.5 - 4.5 ratio :
The thyroid is a major gland responsible for full body synchronisation, your mental, physical, emotional, psychological, and spiritual wellbeing , your inner central heating system and your metabolism. The thyroid is the conductor of all your bodily mechanisms and sometimes one can experience " odd " seemingly unrelated symptoms when one's body isn't balanced and optimal.
P.S. I think in primary care doctors only test your TSH at review. This is a totally pointless blood test, when on thyroid hormone replacement, and especially when you are without a thyroid, or with an autoimmune disease.
As you are to see a consultant, I would hope a fuller blood test of T3 and T4 would be undertaken, but I don't know, as I think if you look to be getting on " with things " proper blood testing seem to be seen as irrelevant.
I read blood tests cost under £1 each, but I have had to resort to getting private tests for my own situation.
I'm with Graves Disease post RAI thyroid ablation in 2005 and now self medicating as I found no help or understanding within the NHS as to my ongoing health issues and unwellness.
As pennyannie says .....FT3 test costs only 92pence on NHS......but they refuse to test for majority of patients......in part because if result shows low FT3 then NHS wants to avoid prescribing T3
Your GP may agree to test vitamin levels.....but if not get these tested privately too alongside full Thyroid test
Alway get blood test as early as possible in morning and before eating or drinking anything other than water and last dose Levothyroxine 24 hours prior to blood test
Your weight increase suggests your either a poor converter or not on high enough dose of Levothyroxine
New NHS England Liothyronine guidelines July 2019 clearly state on page 13 that TSH should be between 0.4-1.5 when treated with just Levothyroxine
Note that it says test should be in morning BEFORE taking Levo thyroxine
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 doctort please email Dionne at
tukadmin@thyroiduk.org
Professor Toft recent article saying, addition of small dose of T3 may be necessary for many. Note especially his comments on current inadequate treatment following thyroidectomy or RAI.
Slowdragon, I am really shocked that a "FT3 test costs only 92pence on NHS" and rarely, if ever, is tested and is very informative when patient isn't recovering as they should.
That is awful and shows just how those in 'power' are not even aware of the importance of the 'frees' and instead of concentrating on the TSH (whoever thought of that as being more important rather than symptoms and the frees) they don't give a thought of how best to relieve all symptoms (not one at all) but they provide 'other prescriptions' to control symptoms, i.e. anti-depressants etc. What about all the patients who lose their livelihoods due to insufficient support from doctors/endocrinologists and made to feel it's their own fault.
We need more compassionate and knowledgeable doctors . like Dr Skinner and Dr Peatfield and others who lost their licences for doing as they were trained as students. Imagine doing what you were taught as a student then hauled before the GMC for doing as you were taught i.e. before the introduction of blood tests. It wasn't patients who complained to the GMC.
Not including the withdrawal of NDTs through False Statements and then T3 - expense for that was the excuse. No thought given to all those who had been prescribed previously and without any warning - what stress/panic was caused.
Well seen, they don't really have any knowledge as Dr and Dr S did and all doctors in their era.
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