1327431 tn?1327072104

normal range

What is classed as a'normal' range for FT4 and TSH , for underactive thyroid
I never seem to get my FT3 tested
answers would be great thanks x
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Avatar universal
They should give you the range for FT4 when you call for test results.  You need to know the position in the range, not just the result.  If possible, always get a copy of the lab report and write on there how you were feeling and your med dosage at the time.  These become very valuable for future reference.  Also, I would lean on them hard to do the FT3 test.  Explain that you are aware of the possibility of inadequate conversion of T4 to T3 and want to make sure of your FT3 level.  

Yes, my thyroid status is pretty stable, now that I am again able to obtain Armour thyroid and get my dosage adjusted adequately.  At one time years ago, I was on a T4 med, and had the T4 to T3  conversion problem.  Even though my FT4 was high and my TSH very low, I still had lingering hypo symptoms.  When I learned about the importance of FT3 and got mine tested, it was low in the range.  My meds were changed to include T3 and now my FT3 is in the upper third of the range and I feel best ever.  
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1327431 tn?1327072104
Yea i do get hair loss but nothing to extreme , Em just tired , (energy levels) sleep pattern , Nerves somethimes ...finding it hard to get the right dose , if i take too much levothyroxine i go over active and take too little i go under , feel bloated alot , crabbit lol
But i will be honest i do feel better than i did a few months ago so fingers croosed i might be on the way up :)
Can i ask is your underavctive thyroid stable ?? And what kind of things do you do to get it right iam half way there , but advie would be great

I dont have lab results i just phone them and they tell me my T4 TSH , banging my head off a brick wall get FT3 but i will keep pushing :)

Due another one in a couple of weeks heres hoping .....

I dont regret taking RAI back last July i dont know how i put up with over activity for so long , much better controlled under activity , just worried i put on too much weight if not on the right dose .... Read alot of that on here ....

Thanks for you advise , gimmel and FTB4 :)
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Avatar universal
Do you have the reference range for the FT4 test?  Results and ranges vary from lab to lab and it is important to know where your result falls within the range.

Sounds like you need to ask why you don't get the FT3 test.   Maybe the doctor has to request to make it happen.  You might tell the doctor that patients who are on T4 thyroid meds frequently have suppressed TSH levels and low FT3 levels due to lack of conversion of T4 to T3.  Since FT3 is the biologically active thyroid hormone that is largely responsible for metabolism and many other body functions, you need to get tested at least once find out about the conversion. If FT3 is low in the range, that is consistent with being hypothyroid and for most patients indicates a need for an  increase to the upper part of the range.

When (Note that I say when, not if) you get your FT3 test done,  if it confirms as low in the range, then your next battle will be to get a source of T3 added to your meds.  This can be a combo T4/T3 type in place of your T4 med or it could also be an addition of a T3 med like Cytomel, to your T4 meds.  A good thyroid doctor will treat you clinically by testing and adjusting FT3 and FT4 levels as necessary to relieve symptoms, without being constrained by resultant TSH levels.  Symptom relief should be all important, not test results.  Test results are valuable mainly as indicators during diagnosis, and afterward to monitor FT3 and FT4 levels as meds are increased toward symptom relief.

While discussing FT3 with your doctor, you might also talk about how low levels of iron/ferritin, zinc, and selenium  can adversely affect conversion of T4 to T3, and the advisability of testing for those.  I'm sure your doctor will just love that conversation.   LOL

By the way, what symptoms are you having besides the hair loss?
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Avatar universal
There is no normal range with thyroid, every person has an optimal range where the have no symptoms, the problem today with thyroid is that many mds still use an old reference range for TSH as an example, some go by .05 to 5.5, some 0.4 to 4.5 and the better one use .03 to 3.5, this is due to the fact that these ranges were just statistics based on reported cases of thyroid diseases, and today there are so many more cases in addition to so many unreported cases, so they have not changed these reference ranges accordingly, MD's should treat by Free T4, Free T3 and the patients symptoms, not on TSH, Tsh is a Pituitary hormone, The Free T3 and T4 are the ones that should guide treatment and dosage, I would insist on the Free T3 and Free T4 tests in your next lab work. In general with Hypothyroid or Underactive, your Free T4 should be about mid range, Your Free T3 should be higher than the Free T4 and about 2/3rds of the range, You TSH shouls be supressed (1.0 or less) This is not exact, but is were most are comfortable at with symptoms for Hypoactive.  If you get your Free's done, post them with the reference ranges and we can give you a much better opinion and comment   Best Regards and welcome to the forum FTB4
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1327431 tn?1327072104
Thanks for your post i totally agree with you , I try everytime and get my FT3 tested and never seem to get it done in the UK , on my blood sheet it just has FT4 (strange)
Even when i go to labs i ask them to add it (they do) and still dont get anywhere
I will keep trying :)
I feel much better than i did before
I got my hair tested because i was at the end of my tether with all of it felt so poorly at 30 years old , I  wasnt getting anywhere , And then i found out my digestive system wasnt working right .... my food wasnt absorbing correctly so they gave me digestive Vits to take with my food , also came up how low my energy levels where ! All i needed was a decent multi Vit
The berrocca i was taking didnt help ....Its amazing how diff you can feel ...when changing to the correct Vits  !!

My lastest blood result was
FT4 - 12
TSH - 00.2
Dont know if that helps but think its better than my last one

FT4 - 27
TSH - 00.1

I will keep pushing for FT3 ...........thanks
Helpful - 0
Avatar universal
To me, FT3 is the most important test because FT3 largely regulates metabolism and many other body functions.  Studies have also shown that it correlated best with hypo symptoms, while FT4 and TSH did not correlate very much at all.  Doctors seem reluctant to test for FT3, on the assumption that if they know FT4 then they can estimate FT3 adequately.  This is often not the case, because of poor conversion of T4 to T3 when taking thyroid meds.  In view of the importance of FT3, why not just test and be sure?

So, I suggest that you should request FT3 again and insist on it happening.  I even go to the extreme of making sure that the lab people are aware that it is to be tested, to make sure they don't overlook it.  

As far as ranges, they can vary from lab to lab.  Over 8 years ago the AACE recommended that the range for TSH should be revised from .5 - 5.0 down to .3 - 3.0.  Unfortunately many labs and doctors have yet to adopt the new range.   For FT4 I have seen 3 different ranges, .60 - 1.50 ng/dl, .8 - 1.8 ng/dl, and 10.2 - 19.2 P mol/L.  
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