Reduced levothyroxine which increased T3!

[Tina_Maria]

So I have done a little tweaking with my medication recently. I have had Hashimoto's since 2003 and have been on 100mcg levothyroxine for a long time. I need to run my T4 levels quite high, so I can get a good level of T3. Obviously not ideal, but only this way I can be quite active and function properly. My TSH has always been suppressed since I was on the 75mcg dose and has never budged much.

Over the last few years, I have noticed that my conversion gets less efficient and has gone down a bit, so recently I have decided to reduce my levothyroxine by 25mcg per week to see if the T4 comes down a bit and my conversion will improve (which surprisingly it has!).

I should also mention that my ferritin is good, so are folate, Vitamin B12 and Vitamin D - so no worries on that front. I am also on HRT and this is going well too (no changes).

I have been on the reduced dose since the beginning of Jan this year. I will include the previous tests as well, so you can see the trend.

April 2021

TSH <0.01 (0.27-4.2); T4: 23.6 (12-22) 116%; T3: 5.7 (3.1-6.8) 70.3%; Ratio: 4.14

August 2023

TSH <0.01 (0.27-4.2); T4: 24.2 (12-22) 122%; T3: 5.5 (3.1-6.8) 64.9%; Ratio: 4.4

September 2024:

TSH <0.01 (0.27-4.2); T4: 23.0 (12-22) 110%; T3: 5.0 (3.1-6.8) 51.4%; Ratio: 4.6

31/03/2025

TSH <0.01 (0.27-4.2); T4: 21.3 (12-22) 93%; T3: 5.3 (3.1-6.8) 59.5%; Ratio: 4.01

I felt quite good on the previous dose with no problems, however, now I feel a bit spaced out and my concentration is not as good as before, which is surprising, as my T3 has come up slightly, so this should really have helped?

I cannot reduce the levothyroxine any more at present, as I have done this about 7 years ago (100 and 75mcg every other day) and felt very unwell, so don't particularly want to go there again.

So the question is, should I try to ride this out for a while longer and see if this dose will settle eventually and perhaps the T3 comes up a bit more?

Or should I go down another path and reduce the levothyroxine a bit more and adding in some T3 into the mix, even though the conversion rate has improved quite a bit since the last test?

Any ideas or suggestions welcome!👍

[greygoose]

It's not surprising that your conversion has improved slightly because with a lower FT4, less of the T4 will be converted to rT3, and therefore more to T3.

[Tina_Maria in reply to greygoose]

Yes I thought that would be the case and quite interesting to see. Question is though, why do I feel less good if T3 has improved and the conversion has improved? Before I did the test I was convinced that my T3 would have gone lower than at the last test, as I have the symptoms of low T3 wooly head, slight brain fog, concentration difficulties.... its puzzling!🤔

[greygoose in reply to Tina_Maria]

I don't know it could be something to do with the deiodinase that's doing the conversion. I don't understand it enough to explain it to someone else but it should resolve with time.

[SlowDragon Administrator]

Retest again in another 6-8 weeks

See if levels are steady or continuing to drop

[Tina_Maria in reply to SlowDragon]

Thanks - just hope that wooly head will go away! 😂