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Can I use total t3 to judge an increase in T3 meds?


My doctors called me in for my annual monitoring test and as I told them I was taking privately-obtained T3, requested a T3 test and the labs did it! unfortunately, they did a Total T3 test instead of FT3.

I'm wondering if I'm still able to use that result to judge an increase in T3?

I currently take Levo 100mcg daily and alternate Tiromel 6.25 and 12.5 every other day. I'm thinking of upping it to half a tablet each day (12.5).


4/9/17 NHS

TSH (0.2 - 4.0) 1.0

FT4 (10 - 20) 13.6

TT3 (0.9 - 2.5) 1.3

Previous results:



TSH (0.2 - 4.0) 0.17

FT4 (12 - 22) 16.7

FT3 (3.1 - 6.8) 4.34



TSH (0.2 - 4.0) 0.19

FT4 (12 - 22) 19.35

FT3 (3.1 - 6.8) 5.87

17/6/16 NHS

TSH (0.2 - 4.0) 2.1

FT4 (10 - 20) 14.5

TT3 (0.9 - 2.5) 1.4


I feel much better for taking the T3. However, over the past week or two, correlating with some medium-high stress which had me signed off from work for 10 days, I've noticed a few symptoms like extra tiredness, the odd 'palpitation'/heart area fluttery rumble and a little bit of insomnia. I was wondering if this was thyroid related (i.e. hyper), but then looking at my results I'm not sure it is!

Also, looking at my results - as I add more medication, my levels seem to be reducing which is the wrong way?! But I'm feeling better? So confused!

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Hi - if you left 8-12 hours between your last dose of t3 and the test, then your recent symptoms are due to overmedication rather than under. One is as bad as the other. And you have been over for a while as in Jan 5.87 against max 2.5 and June 4.34 with same max. Have you any results from before taking t3? What prompted you to add t3 to t4?



ARGH - how do I edit my original post?! I left the TT3 ranges in the FT3 box.


Ah, that makes sense! Click on the down arrow in the box on right at bottom of post and click edit.


Found it - range for the FT3 tests changed to 3.1 - 6.8.

16/1/17 is before taking the T3.

I wasn't feeling fully well on 100mcg T4 plus vitamin supplementation and was tired of fighting the doc. Thought I would give T3 a go in addition to T4 following advice on here. Feeling much better and capable, but blood tests are confusing.

All tests were 24 hours after T3 and 36 hours after T4 due to taking Levo in the evening and Lio in the morning. Maybe I need to join them again. Also tests done at around 8:30am each time.


Well in that case even your ft3 figures aren't really accurate anyway. You really need to change pattern of taking t3 before test so that it is taken evening before rather than leave 24 hrs.

However, your results were actually better previously, in the January results. You may actually have found that your symptoms started to improve given a bit of time at that dose, rather than chop and change. But that is spilt milk now! Even though you don't have an ft3 figure for your last set, the fact that Tsh is now higher could suggest that your ft3 has actually lowered. That could be a function of your own thyroid 'relaxing' a bit because of the extra t3, in which case a dose increase would certainly help.

Your pattern of different doses on alternate days may be to blame for some of your issues, however, as t3 has a much shorter half-life than t4 and hence should be dosed evenly.

What are your nutrient levels like? T3 is a hard taskmaster and your recent issues could be due to some of these being used up faster and hence levels declining, combined with he effects of raised cortisol caused by external stress.




I had been at the January dose of 100mcg levo for quite a while - months, if not a year or two. With the T3 I started quite slowly with a dose, and wasn't aware that different doses on alternate days was an issue with T3 - I think I've seen posts about alternating T4, but then as that has a longer half-life I can see why it shouldn't be applied to T3.

Previously to adding T3, all my bloodtests have been at around 8am, even when I moved to an evening T4. From what you're saying, is it best to have a test a period of time after my last dose, rather than at the same time as I've always tested? For example, 24 hours after last T4 and 12 hours after last T3 (which I only take once a day in the morning) in which case I'd be taking the test in the evening now?

Nutrient levels need another retest. I was low on Vit D which got back up to just over the lower threshold earlier this year from the docs, and now I am continuing to try to bring it up over 100. My B12 was about halfway through range, so for a period of time I was supplementing B12 and B Complex, I think i'll start those again. Need to check on Iron again.

Thank you for your help!


No problem, you're very welcome.

On the tests, no don't do them in the evening, stick to the morning. But do adjust when you take your doses. Since you normally take levo in the evening, just skip your dose the night before test and take it immediately after test instead. I would be inclined to switch your t3 to evening dosing for a couple of nights before test. That should have it at a reasonably steady level on test morning. And yes do try to even your t3 dose out. T4 timing is much less sensitive because it has to be converted by the body (predominantly in liver) before becoming the active form. So the body itself produces a steady flow of the active t3 form.

Good luck, hope you feel better soon.



Have a look at this post :


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No. Total T3 isn't a useful test. You need Free T3. As Diogenes pointed out in a previous thread, people have vastly different amounts of binding proteins so the total figure doesn't have any obvious relationship to the Free figure.


Thank you!

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