Thyroid UK
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Increase in T3 raised my T4 blood level... why would this happen?

Hello. Quick question you guys might be able to help with...

I was taking 150mcg levo and 15mcg T3, blood results were T4: 12 T3:4.7

Then left levo the same but upped the T3 to 20mcg: bloods T4 21.9 T3:6.2

Now, I get why the T3 result has gone up a bit, but why the big jump in T4 when I've not increased levo? Any ideas? Thank you. : )

7 Replies

Well, I would imagine that as you are taking T3 orally, the body needs to convert less of the T4 to T3, so the T4 is mounting up. Maybe you could reduce the levo a little.

I'm not a doctor, but that's how I see it.

Hugs, Grey


Thanks Grey, might try taking the levo down by 25mcg to start with and see how it goes. x


That would be my gues too :) xx


Your Levo does seem quite high. I'm no expert but was on 175mcg Levo which is being reduced to 75mcg to make way for 20mcg Liothyronine (T3)...


Thanks... might try a T4 reduction experiment. Good luck if you're starting T3, it really does make a difference. I'm a long way from getting it right but it is defo better than levo alone : )


Sorry, one more question: the top end of the range for T3 is 8.0 so I could push the T3 up a bit (I'm still not feeling great, tired, cold etc) but if it looks like the T4 isn't converting that well what about a bigger drop in T4 (say going down to 75 or 100mcg) and upping the T3 a little bit incrementally?


May be worth starting a new question if you get no replies - comments can get missed. :(




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