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Latest test results after taking t4/t3 any advice welcome

TSH - 0-008 (0.27 -4.20)

Free t4 13.6 ( 12 -22.0 )

Free t3 5.39 (3.10 - 6.80 )

Have been on levo 75mcg + t3- 3×5mcg daily for six weeks. Blood test done early morning fasting, levo taken 24hrs before and t3 taken 12 hrs before test.

This is the first time I've taken a t4/t3 combination which was prescribed by my endo as I've been on t4 for the past 8 yrs now and dispite altering my dose I've never been really well on it. I do feel better in some ways, less brain fog mood swings gone, constipation gone but I still have dizziness and still feel fatigue.i think my t3 levels look good but not sure my t4 level should be that low so any advice would be very helpful as I will be going back to see endo next week and would like to be prepared, thanks so much in advance for any help you can give me .

7 Replies

Hi Raventhorpe. I had the same issue when I started on combination T4/T3. My dr insisted on me reducing T4 to 75 mcg when I increased T3, and my T4 ended up too low. When I increased the T4 back to 100mcg I felt better.


Hi Maggie 0652 I thought that my t4 was too low but wasn't sure if that was normal when taking t4/t3 combo so will trying increasing my levo back to 100 and see how I feel. Thanks for answering me.



We're all different in where we need our FT4 to be when on combination of Levo and T3. I need my FT4 over half way through range, others do well with it much lower, so we need to tweak doses to find our best place.

Your results show that there is room to improve your FT3 so an increase in T3 could be what you need to feel well. Whether your endo will agree is another matter. They don't seem to like going above 20 so you might be lucky to get an extra 5mcg.

But an increase in Levo to bring your FT4 up higher in range could also be the answer, if you still have some natural conversion then your FT3 will rise as well as your FT4.

Are you vitamins and minerals at optimal levels, ie

Vit D - 100-150nmol/L

B12 - very top of range

Folate - at least half way through range

Ferritin - minimum 70, preferably half way through range


Hi Seaside Susie, I will see if endo says i can have extra on Wednesday, feel I was lucky to get any t3 prescribed on NHS with the way things are at the moment, but as I do have some natural conversion I could try the t4 if endo won't give me any more t3. The last time I had my vitamins checked was in Dec I was supprised that I did have a problem with my vit D it was right at the bottom of range as I had a month in Spain but did a course of supplements 5000 also mk 7 /k2 and magnesium for a couple of months and now just taking maintenance dose, vit b12 was over range after supplementing I take b12 spray and Thorne basic B complex daily, but had to stop the b vits for a while due to bloodtest. My ferritin is always over range, I think my folate could do with being a bit higher thou. Thanks for your help really don't know what I'd do without the help I have received from you all.

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You might find vitamin D has dropped right down again. Best to retest.

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Hi slow Dragon I do think I could do with checking my vit levels again but it's the cost of blood tests, I have spent loads this year already and as we are pensioners find it hard to find the money, GP don't seem to want to do the test unfortunately. Will have to get saving😊


Just vitamin D is £29 from vitaminDtest.org.uk

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