Thyroid UK

T3 Slightly Below Range

I was diagnosed with Graves Disease in 2012 and had Radioactive Iodine Treatment in the same year. I have since been battling to feel anywhere near to normal and have just sat down in desperation to graph my blood test results from diagnosis to now.

Interestingly my FT3 was checked regularly up until March 2013. I hadn't realised until now that this test came back below range. The results were:

TSH 0.20 (range 0.35-4.94)

FT4 16.2 (range 9-19.1)

FT3 3.04 (range 3.6-6.15)

I realise that this is only just below range however I am suffering from extreme tiredness, constantly being rundown and unwell and extreme problems with my eyes (although no apparent thyroid eye disease visually).

This low FT3 was never mentioned to me and my FT3 has not been tested since despite me having 3 more sets of bloods taken. The results from these were:

MAY 2012: TSH 0.30, FT4 15.7

NOV 2012: TSH 0.20, FT4 15.5

JAN 2014: TSH 0.37, FT4 15.9

(Ranges as above for all of these)

As my TSH is within range my doctor seems baffled by my lack of well being and has requested a full blood count and haematinics test (I do not yet have the results from these).

I am currently taking 100mcg Levothyroxine and 1600 IU Fultium D3 (Colecalciferol) per day.

Do you think that my T3 could be at all to blame for any of this and is it worth requesting for this test to be repeated.

Feeling very alone and helpless. :(

12 Replies

Have you had your B12, vitamin D, ferratin and folates done too? You need those levels to be quite high within the range to feel good. They make a difference, also how much thyroxine are you taking?

Do you know what your bloods were when you last felt good? I know when I was on block and replace I only had to be a little bit on the low side to feel really bad. An increase in my levo got me back to feeling better.

I was always 'within range' (I just HATE that term!) but I wasn't at my optimal point within the range so I didn't feel good.

Don't feel alone and helpless though, that's what is great about this group and on the plus side you have actually had your T3 measured - many of us haven't - and your doctor seems to be prepared to keep going and do more tests.

You're definitely in the right place for sympathy / empathy and support so don't give up - someone else with more knowledge than I have will hopefully come along soon and explain all about bloods. x


Sorry, have just noticed how much levo you are taking. x


I had TT in 2006, following Graves that would not settle on Carbimazole. I felt unwell for years and in 2012 started to ask more questions. Asked for my T3 to be tested and it was low, just like yours. There is a slight difference in that my T4 was over range, indicating I probably was not converting properly. I went to see an Endo privately to get T3 and have been on it in some way ever since.

I wonder if in your case, since your T4 is not near the top of the range, that you should first ask for an increase in T4. Take it slowly and ask for 125. That is still not a high dose for someone with no thyroid but you may find it makes a big difference and brings your T3 up. If that does not help, you could go to 150 or ask to trial some T3. Of course your GP will panic if your TSH gets suppressed but you could quote Dr Toft, who says this is sometimes necessary to restore good health. I am not a great fan of Dr Toft but in this instance, he says what we want to hear!

Also ask for all the checks suggested by Fruit and Nutcase, as these are important for processing thyroid hormone, although you will be unlikely to get a GP to believe that.

Hope you begin to feel better soon and if you do get T3, be aware they will probably reduce your T4 by 50 mcg, which sadly usually brings you back to where you started. That is why I suggest getting T4 up higher first!


Hi di you feel better niw since t3? Similar story fir me graves tt :2007 never felt well just ordered private blood tests. Do you ask did fir referral to private endo I'm looking after me niw I'm nit settling fir less even if l have to pay! X


Yes, I do feel better but still not like I was before Graves started. I do not think it is possible to be normal again with TT. I asked for a referral to the endo, who was hopeless by the way. I have never met a good one, have you? Dr Skinner was my saviour. He let me try different doses and learn what my body needed.


Hi I only ever seen one then once I had tt I was practically dumped! To the gp! X


Yes, that sounds like mine and I was paying for it too! Dumped is the exact word to describe it,


He told me befire op I'd still have dealings with him because of eyes....... Never seen him again lol do you still have problems? I hate my puffy lids l hate I've been left like this it affects me so much x


Hi As said you need all the other tests. However, obvious to me that you need some T3, some docs are against it and some hospitals, so you need to check and change if this is your case.You must feel terrible, if my FT3 is even low in range, I do. I have to have armour ( cannot take levo) and T3 too, good Endo.That could be that you need a little less T4 too as , that is fairly high in your range, but that is for the future.

Best wishes,



Thank you for your reply Jackie. Annoyingly I was released from my Endo last month as my TSH and FT4 were all in range and a lot of my symptoms had cleared up. My tiredness, immunity to illnesses and eyes however have been an ongoing battle which she seems to have washed her hands of. I will have to pursue this with my GP. Do you think it will need a new referral to the Endo?


Hi This can happen usually FT3 is the problem, if establshed on the right treatment,depends on the Endo but usually if e mail endo via their sec. an e mail to be sent on to the Endo and explain. Then they will se you, if within a year without asking GP. If difficult, you may need the gP to write again.

Things can change. Are you sure your iron.ferritin is Ok? B12 high in range? Had a recent diabetic test. Vit D ( hormonal) and calcium? Any of these could be the problem, all hormonal and mostly autoimmune too.Usually if thyroid is right, you have less infections.

Best wishes,



Thank you for all of your replies.

I am waiting for B12 results at the moment, last February they were 315 though (187-883). Vitamin was 36 in February 2013, I am not taking daily supplements and my Vitamin D was up to 111 (>75) in November so I think that's fine now. Ferratin was 20.1 (10.0-204.0) in February 2013 but hasn't been checked since.

My main problem at the moment is the tiredness and problems with my eyes. I am seeing an Opthamologist for the third time tomorrow but so far she has been useless. They can't find any problems with my eyes yet I am having so many symptoms that it affects me every single day. There must be something that some health 'professional' can do?? :(


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