Low ft4, out of range high ft3. Confused - Thyroid UK

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Low ft4, out of range high ft3. Confused


Very confused. Can anyone suggest a cause for ft4 being down at 11.7 and ft3 being out of range high at 6.0? (TSH at 2.4 and rising) Anti-bodies 'normal' 9 when abnormal starts at 70.

GP scratched her head and could only suggest she speak with an endo for advice. Never been on meds but all the symptoms of hypo, no eyebrows, swollen tongue, digestive probs and hair loss not to mention the insessant cold and fatigue.

I have read about pooling (depleted t4 output is compensated for by t3 for a while or unused t3 remaining in the system due to poor take up probs and not exctreted).

Would there be any point of treatment and what would it be likely to be?

Any help at all would be most appreciated.

10 Replies

Hi As far as I know ,I would say that you definitely need treatment with thyroxine , which is T4. Are you sure of the ranges as my FT3 is just under 6, That is just in range.at my Lab. I am on armour and T3, What about your vit D? That is hormonal and effects the thyroid, no one knows quite how!Have you had other hormones tested? You certainly sound as if you are Hypothyroid, it does not necessary have to be auto immune, although often is. I would also ask for a minimum of U`s and E`s ( kidney function ) , b12 and Folic acid and ferritin, usually done in FBC although there is a better test. If D low then you need a calcium test before treatment and best from GP ( or better endo)Sometimes thyroid disease is hard to diagnose, which is why we all have such problems with it initially. When I had treatment years ago ( after a battle) it was only my FT3 that was very low then.Now it is usually about tSH , which is all down to cost. The other thing that springs to mind is you need other endocrine tests,I am thinking of the underlying problem may be some thing like Parathyroid etc etc. It would be a good idea, Also a thyroid ultra sound. I think ,to ask for a referral yourself to a good endo, if GP still not sure. If you see an endo, make sure you do all your research do not just see one of the GP`s choosing.

Best wishes,


If you want to reply to some one click on " Reply to this".

tulula59 in reply to Jackie

Hi Jackie

The ft3 range is up to 5.7 at our lab so 6.0 is a def out of range. Vit D - have been taking 3000iu daily for two years due to osteopenia plus 900mg calcium, mag and zinc. Old kidney function tests 2 yrs ago all showed ok, s did folate and B12. No other investigations have gone ahead as they have always said it was due to being hypermobile, food intolerances and going through the menopause.

Am seeing Gp again tonight and want a referrral to endo but still trying to find a good one so as not to waste my time.

Thanks for the input though.


Jackie in reply to tulula59

Gilly, If private ,any one in the country. If NHS, look on all your hospital sites, cross reference to private hospitals and then look up individual CV`s, that gives you a good idea ,and of course, if possible ask around, you need a good one.I have found asking people, sometimes they mean "nice" not necessary "good".

Best wishes,


I have been on 50mcg levo for the past 6 months and have the same scenario with my last blood tests. The endo did not seem bothered that i had high tsh, low t4 and high T3. I was bothered though and have seen a private doc who has tested me for reverse t3. Am waiting results on this test.

greygoose in reply to lizzie1

Was it your FT3 that was high? Or total T3? Because if FT3 was high you're unlikely to have a problem with rT3, I would have thought. Strange...

Lizzie - Interesting. Do add your results to this thread please. I owuld be very interested to read them.

Jackie - Am desperately trying to find out the name of one at Sailsbury Dis Hosp as there are 2 there and one is recommended (username zarjaz) but which one I wonder. I commented on the thread on here about Sailsbury but no replies. Shame.

GP appt tonight so will not have any names to suggest but I will get cracking and try to find the CV's for both there and see if that gives me any pointers.

Thanks for the input.

lizzie1 in reply to tulula59

Hi again

My results blood test results whilst on 50 mcg levo were

TSH 5.49 T4 11 (7-20) FT3 5.5 (3.3-5.3)

The endo said that there was not a problem as I had "plenty of T3". Why then do I feel like I am 100 I asked. Probably the menopause was the reply and she promptly sent me on my way.

The endo did say that as I felt so rubbish on levo and was considering NDT that I had to be careful as the T3 in NDT could send me over the range.

Really dont know what to think!

If I have such a healthy supply of FT3 why do I feel so awful.


tulula59 in reply to lizzie1

I think the thing is that if someone could confirm that being menopausal is the reason why we really do feel so dreadful and that this will pass (only been 6 years for me so far!) then I could take hope from this.

It's the fact that the endo has now said that such a low ft4 and high ft3 is 'not significant' that bothers me when I feel so damn awful. He's also said that loss of eyebrows, hairloss and feelking cold so much is due to being hypermobile! I've never heard such rubbish in all my life!

I'm going to write to the Ehler Danlos people and see if I can get anyhting in writing that these are NOT symptoms of EDS.

greygoose - it was my FT3 that was 6 (range 2.5 - 5.7). FT4 is dropping all the time and TSH slowly rising now at 2.4. I'm really wondering why I should have so much FT3 in my blood when FT4 is so low and all of my symptoms are hypo.

I have read that FT3 can 'pool' if not taken up by tissues and that the thyroid can over compensate for loss of t4 by producing more t3. it's just that I was diagnosed with fibro three years ago and I'm really not convinced that this was a suitable diagnosis.

It was by a pompus rheumatologist who gave this diagnosis when every symptom that I had could have easily been thyroid. Now on my insistence my bloods have come back saying this.

Who is going to actually care though I don't know!

magicknuts in reply to tulula59

Hi tulula59,

did you ever find out about this?

sorry to bring up an old thread I am interested as I too was diagnosed with fibromyalgia (2 years ago) and became completely asymptomatic for fibro (if was heaven!) due to my previously diagnosed (5 years in remission) graves disease kicking off, I insisted on block and replace again and have been on carbimazole, just got bloods test results and am now underactive.  

My TSH is high (14.1) and FT4 is low (7.9) as expected but my FT3 is near the top of the range (5.0 ref rang 3.6 - 5.4) and all my symptoms back for fibro (I can't tell the difference between fibro and hypo).  It cannot be due to menopause - I am 34 and he also did tests that would have told me if i was menopausal, they came back ok.  I too was wondering why I feel so bad if my FT3 is great!  I also feel my fibro diagnosis was incorrect and hormone issues are more likely but my consultant was so (gggrrr forget the word, but he even started telling me how they diagnose fibro, like dur think I know that mate!)  really worried he won't investigate further when I want to know why my fibro disappeared when I was hyperactive.

So confused by my test results!  guess wait and see if levothyroxin doesnt help me feel better (I am doubtful it will) then I really hope he will investigate further.

I hope you have your answers and feel better

xx Sara

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