CFS & rT3 - GP totally uninterested: I went to my... - Thyroid UK

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CFS & rT3 - GP totally uninterested


I went to my GP yesterday to ask for annual thyroid blood tests. Showed her the Frontiers trial results showing CFS could be caused by rT3 build up. Not interested - as I expected and of course wont add the rT3 blood test. Having looked thru all my blood test results I have never had rT3 tested, so now is the time. Feeling totally defeated today.

19 Replies

I don’t think rt3 is available as a blood test on the nhs. There may be the odd specialist centre but ordinary DGH’s can’t test for it.

topaz1 in reply to cjrsquared

Hi, yes I will have to have rT3 tested privately. Am seeing the Naturopath this next week so will discuss with her.

And, if you have a test and find that you have high rT3, what are you going to do about it? High rT3 results just indicate that there is a problem. They don't tell you where the problem is. And, it depends on what the problem is, how you lower the rT3. There is no proof that rT3 itself causes any problems.

High rT3 can be caused by many things - low/high cortisol, low ferritin, some sort of bug, a starvation diet... One that is often seen with people on thyroid hormone replacement is high FT4 and low FT3, due to poor conversion. Are you on thyroid hormone replacement?

Seems to me it would be better to check out the possible causes of high rT3, rather then spend all that money on an rT3 test which will give you very little useful information.

Point taken Greygoose, clutching at straws!

greygoose in reply to topaz1

I read somewhere that people with CFS usually have low FT3. So, I would think the tests to go for would be TSH, FT4 and FT3. Have you had those done?

topaz1 in reply to greygoose

My GP has agreed to do TSH,FT4 and FT3, B12, ferritin, folate, vit D

greygoose in reply to topaz1

Well, that's great. That should give you some answers. :)

SilverAvocado in reply to topaz1

That sounds like a very useful set! Perfect, even.


For full Thyroid evaluation you need TSH, FT4, TT4, FT3 plus TPO and TG thyroid antibodies. Plus vitamin D, folate, ferritin and B12.

Essential to test thyroid antibodies, FT3 at same time as FT4 plus vitamins

RT3 is an extra test available and you will need to pay for blood draw, not available as finger prick option

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 ideally be done as early as possible in morning and fasting. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)

If antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease).

About 90% of all hypothyroidism in Uk is due to Hashimoto's

topaz1 in reply to SlowDragon

Thanks SlowDragon I'll have a look at those tests. I have been diagnosed with tpo and tgo antibodies.

SlowDragonAdministrator in reply to topaz1

So if you have high thyroid antibodies this is Hashimoto's also called autoimmune thyroid disease

Can you add your results

Essential to test vitamin D, folate, ferritin and B12. Always get actual results and ranges. Post results when you have them, members can advise

Hashimoto's affects the gut and leads to low stomach acid and then low vitamin levels

Low vitamin levels affect Thyroid hormone working

Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

But don't be surprised that GP or endo never mention gut, gluten or low vitamins. Hashimoto's is very poorly understood

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies

Ideally ask GP for coeliac blood test first

topaz1 in reply to SlowDragon

Thanks for all the links SlowDragon I'll have a look at them. I'm having the tests you mention in about 2 weeks so will post the results. I do have Hashi's and have been gluten free for about 3 years and I take digestive enzymes for low stomach acid.


The following is by a doctor who was also an Adviser to TUK.

He was an expert on Thyroid Hormone Resistance too . He died through an accident. This is an excerpt from a paper he published and Thyroid Resistance patients recovered with T3:-

Some of our patients who clearly had resistance and fully recovered by using T3

(within the context of metabolic rehab) were free from mutations in the gene.


Resistance may result from several possible mechanisms (for a full description, see Chapter 2.6,

The Metabolic Treatment of Fibromyalgia, pages 303-313, 319-321, 323-329

[1]). Regardless of the cause of a patient’s resistance, our current statistics suggest that

34% of our patients with a diagnosis of fibromyalgia have resistance.


Unfortunately, we can’t determine when we first evaluate a patient whether she has thyroid hormone resistance. We can only suspect that she might. If she has a diagnosis of fibromyalgia, chronic fatigue syndrome, or ME, this means that she has symptoms typical

of hypothyroidism or thyroid hormone resistance.

topaz1 in reply to shaws

Thank you shaws. I read thru the link you gave. I've been diagnosed with chronic fatigue syndrome for 23 years and Hashi's for 4. I have taken Armour and Nature-Throid neither of which made any difference to my symptoms. I remember taking 2 1/2 grain N-T and increasing by 1/4 grain and being over medicated! I'm taking Metavive IV but again symptoms remain the same. My previous NHS GP who first diagnosed Hashi's is now private so I might go back to him?

shawsAdministrator in reply to topaz1

Dr Lowe only prescribed NDT but T3 for his thyroid hormone resistant patients. He himself took 150mcg daily (in the middle of the night) which enabled him to research etc and helped people who were undiagnosed but had disabling symptoms.

Levothyroxine didn't do me any favours at all. In fact was far worse than before being diagnosed with a TSH of 100. T3 added to T4 made a difference as did NDT but T3 resolved all my symptoms, thankfully. This is another link and there are topics at the top of the page. Some may not be accessible as it is now archived due to Dr Lowe's demise.

Jacs in reply to shaws

Hi Shaws - this is a really useful link. I've tried to access some of the other chapters of Dr Lowes book through Wayback Machine but can't get past the initial summary page. Any advice?


shawsAdministrator in reply to Jacs

No, you cannot access any others. These are just three chapters that his widow posted. Unfortunately, when Dr Lowe died his work was archived and website closed. I shall give you the link I have with more articles of interest. He knew what he was talking about and is a great loss.

Jacs in reply to shaws

Thank you 😃

I also don't think rT3 is available at all on the NHS.

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