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Ft3 3,6 pg/ml, rt3 155,9 pg/ml

Ft3 3,6 pg/ml, rt3 155,9 pg/ml

I know i should divide the ft3 and the rt3 numbers and the result should be between 10 and 20.

3,6/155,9 = 0,023

The reference numbers of the lab say between 90-215 rt3 is ok.

Why is my numbers so low, is it right to divide rt3 in piktogram or is nanogram right?

If i keep ft3 in piktogram and rt3 in nanogram is get this:

3,6/0,15= 24

Which seems to be a ok number.

Can someone please tell me if i got to much rt3 or not?

6 Replies

I take it you're trying to calculate your rT3 ratio, there. Waste of time. However, what we do need are the ranges for FT3 and rT3.

Your rT3 is probably high and your FT3 too low, which skews the ratio. And, your rT3 is probably high because you're a bad converter and there's too much unconverted T4 in your system which is obviously going to convert to rT3. So, what we really need to see is your FT4 and FT3 with the ranges. And, that's all. :)


You can see how to work out your ratio here and yours comes under Example 4: tpauk.com/main/article/how-...

The FT3 is not in the hundreds, so we have to multiply by 100 AND the RT3 is in the hundreds so we have to multiply by 10, so we have to multiply by 1000 overall.

so that gives 3.6 x 1000 = 3600 divided by 155.9 = 23

and that article says a ratio of over 20 is good.

However, this is your first post so we don't know anything about your thyroid journey or what meds you're on or what your thyroid test results with ranges are like. Maybe your FT4 is way over range and making rT3 instead of FT3, we don't know. And illness can raise rT3 as well. So lots involved and we don't know what might apply to you.


ft3 10,1 pmol/l (Range: 4,09 - 6,65)

ft4 28,4 pmol/l (Range: 13,1-21,3)

I was taking Novothyral (100T4/20T3).

I think i will switch to taking 20mg Levo T4 and 20mg Liothyronine T3.


Well, with those results you were way overmedicated. But reducing from 100mcg to 20mcg Levo in one go is too big a jump.

As both FT4 and FT3 need reducing, why not just cut your Novothyral into halves/quarters. Start by reducing to 3/4 of a tablet and see how that goes. If after 6 weeks your FT4 and FT3 are still too high, go down to 1/2 a tablet.

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Do you have an idea why i feel Hypothyroidism symptoms even if my ft3, ft4 and rt3 is good?

Cortisol, Ferretin & Vitamins are ok too.

Only thing the doc found is low mitchondrial activity...

Maybe i need to switch to natrual pighormons since they contain t2 which seems to be important for mitchondrials.

Thanks for your help :)


Not really. I had very high FT4 (at one point higher than yours), FT3 about 40% through range, rT3 I didn't test at the time, but I had what seemed to be hypo symptoms. When I tested just about everything I could think of there was an adrenal problem, sex hormones were on the floor, severe Vit D deficiency, very low ferritin and folate but OK B12.

You say your vits and mins are OK, but are they optimal?

Can't help with mitochondrial activity but Dr Myhill has lots on her website you could check - maybe start here drmyhill.co.uk/wiki/CFS_-_T...


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