Thyroid UK
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Unusual (for me) blood test results

In Feb I was taking 75/100 levo and 10 t3.

TSH 0.27 (0.27 - 4.2)

FT4 16.0 (12.0 - 22.0)

TT4 100 (59 - 154)

FT3 4.8 (3.1 - 6.8)

RT3 25 (10 - 24)

RT3 ratio 12.3 (15.01 - 75)

Now I'm taking 50/75 levo and 20 t3. I didn't bother with the bells-and-whistles test for this, just TFT.

TSH 2.99 (0.27 - 4.2)

FT4 11.0 (12.0 - 22.0)

FT3 5.6 (3.1 - 6.8)

So my t3 is better but my tsh is quite high. Bit surprised as tsh is always low (except on the odd occasion when I've been undermedicated). The blood draw was done 12hrs from my last dose of meds.

I feel better on this regimen. I could use a little more t3 I suppose? Any thoughts on how to go forward, or theories on why my tsh is so high? My only proviso is that I'd like to avoid adding levo (thinking it may have been the slightly high rt3 that made me feel unwell on more levo).

13 Replies

is it 75 mcg or 100 T4? T3 does seem low. I'm on 75 mcg T4 and 20 mcg split ie morn and afternoon. But it does depend on your readings. Very difficult to get T3 in the UK as you've probably read. Although my GP has offered me a private prescription at £300 per month. He must be joking. I would urge everyone who is experiencing difficulty getting T3 to complain to the CMA - competition and markets authority. Philip McCormack his email address is on another post but I'm sure you can search on this site. Hope you manage to sort it out


Right now I'm on an alternating dose of 50/75 levo. I'm already being prescribed t3 (for the present anyway, though always waiting for the other shoe to drop).

Currently t3 isn't bad at all - much improved in fact - but there is some wiggle room.

I hear that there is somewhere you can get the private prescription filled but Idk the details. Have you done a post asking if you can get it more cheaply?


I'm just putting forward some random thoughts - sorry I can't be more specific.

In February you had high Reverse T3.

By reducing your Levo dose you will almost inevitably have reduced your Reverse T3.

Does high Reverse T3 suppress or lower TSH? I don't have an answer but it would be interesting to know.

Another theory... Perhaps your pituitary and hypothalamus respond much more to levels of Free T4 than they do to Free T3.


Thank you hb. Am I getting you confused with someone else or were you telling me you were looking into your own slightly high rt3?

Interesting points. I think high rt3 is meant to contribute to a lower tsh, so you may be right. I was under the impression that if your t3 is in the upper end of the range you will inevitably have a low tsh, so this was a surprise.

I do feel a bit better oddly. Not as draggy as on the higher levo dose.


I have had very high RT3 in the past, but my levels will be rock-bottom now because I've been taking T3-only for a year or two.


And do you do blood testing? I think I remember Paul R saying he doesn't bother because the t3 will be high and tsh will be low.


I still do blood testing, but I don't worry about thyroid testing too much now. The things I'm more interested in testing are liver and kidney health, and my nutrient levels.

I do this test about every nine months or so, but it depends on the special offers available for the exact timing :

but only when they have a special offer on, and throw in a free test with it, and then I almost always choose Free T3. It includes phlebotomy which helps, and no posting is required, I just leave the blood with Spire.


Your Free T3 is currently about 68% of the way through the reference range. You have a fair amount of leeway to raise your dose of T3 a bit if you wanted to, I would have thought.


Hb can I ask how you figured that out? I always struggle to understand where my results are in percentages.

I was wondering if I should start taking an extra 5 - 10mcg in the morning - ? (In order to do an early morning test I moved my meds back to the evening, so if I add more t3 I would do so in the morning.) Would an extra 5 be a bit pointless?


FT3 5.6 (3.1 - 6.8)

To calculate the percentage through the reference range :

(5.6 - 3.1) ÷ (6.8 - 3.1) x 100

I just hope the division sign displays correctly.

Alternatively, in English :

(Your result - bottom of range) divided by (top of range - bottom of range) multiplied by 100.


5mcg might be okay. I was increasing and decreasing in quarter tablets for a long time, and it helped me with my experiments.


If I understand correctly you would be on 25mcg per day if you did a 5mcg increase.

There are lots of ways of taking that dose e.g.

Half a tablet in the morning. Half a tablet in the mid/late afternoon, quarter of a tablet at bedtime.

3/4 tablet in the morning, 1/2 tablet later in the day or in the evening.

It really depends on you and how well you do on different dosing regimes. I fiddled for ages, changing timing of doses, number of doses, size of each dose etc.


Yes, it would be 25. I am ready to add more t3 but not ready to do it all in one dose as I get a bit antsy about feeling hyper.

I was thinking I'd leave my current regimen in place (50/75 levo + 20mcg t3) and just add another 5mcg in the morning. It makes it fairly simple. If I feel ok I can tweak it later.

Thanks for your help.

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