I'm on a T4/T3 combo. I recently increased my medication to 100mg levo and 40mg T3 in an attempt to get both T4 and T3 at least 50% through range. However my T3 went over range and my T4 went under range.
Why did the increase cause my T4 to crash and how do I get my T4 up above 50%?
Actual results are:
TSH0.11 (0.27 - 4.2) through range -4.07%
T40.87 (0.93 - 1.7) through range -7.79%
T34.84 (2.2 - 4.2) through range 132.00%
Results are from a US lab as I'm temporally stuck in the USA because of the virus.
I'm aiming to get both T4 and T3 in upper quartile.
Thoughts?
Thanks guys!
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Apollo_Creed
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This is very timely! I am considering reintroducing levo with my T3 but the last time I tried it I “think” (this is my theory) it converts to RT3 and causes me to feel worse.
It’s like the levo (T4) blocks the T3 and I get worse. This is my theory, some folks say RT3 doesn’t cause any effect but every time I’ve had too much levo in my system the RT3 has rocketed and I’ve been worse off.
I can’t really offer you any help other than give this as an explanation. As above what dose were you on before? Maybe you’ve made too big an increase in dose.
I’ll be following to see what others recommend too 😊, you’re not alone!
I'm sorry, MM, but your theory really doesn't hold water. Your T4 will convert to excess rT3 if your FT4 is too high, that's what it's supposed to do. But, it's not the rT3 itself that makes you feel bad, it's having lowered T3 levels. T3 is the active hormone, and will cause symptoms if it's too low.
And, there's no way that levo can block T3. It just doesn't happen. It's all down to conversion to T3 getting worse when your FT4 is too high.
And everything I’ve read states this too but the last couple of times I’ve tried to increase or reintroduce levo I feel awful with aches and tinnitus and various other things, her when I’ve done bloods, there’s no/very little change in FT3.
I can’t explain it, it’s how it feels.
I’d really like to reintroduce levo as I’ve been off it totally for about 10 weeks and it was very low before that, but I really don’t know how to go about it 🤷🏼♀️
I went from 75mg to 100mg levo without any increase in T3. The theory was that it would increase my T4 because it is almost always near 0. Despite increasing levo I failed to increase T4. I don't know why T4 is always on the floor. Perhaps my system does not use the T4 because I'm taking adequate amounts of T3. However many say T3 and T4 should both be in upper quartile and I suspect that is where I need to be but seem unable to lift T4.
. However many say T3 and T4 should both be in upper quartile
That's when you're taking T4 only, not when you on T4+T3. Taking T3 will always lower your FT4. By how much depends on your levels, and how much of each you're taking, and how well you convert. So, what I would try doing is leaving the levo where it is, and lowering the T3 slightly. See what happens.
Ah! Two very good questions. Wish I knew the answers. There was a whole thread on here a couple of years ago discussing why FT4 drops when you take T3, and there were a lot of theories put forward, but none of the really held water. Personally, I just think the body excretes what it feels it doesn't need.
But, then, that wouldn't explain why some people feel they need higher levels if their body is telling them they don't. So, perhaps that theory doesn't hold water, either. I just don't know.
As to why some people need T4 and others don't… Once again, nobody really knows. It's just that we're all different with different needs. There could be a thousand variable that contribute to what we need and what we don't. So, perhaps we'll never know the answer to that. There certainly are no simple answers. Not where thyroid is concerned. So, we just have to experiment until we find what we need as individuals. If we're allowed to, that is.
I only take 40mcg T3 as I can't covert T4 into T3 and of course my T4 is always very very low. However I was under the impression that we didn't need T4?
I have read so much about everyone feels best with your T3/T4 levels in the upper range and I for one have never accomplished this and feel ok ... not without hiccups. I stopped trying now I just go with how I’m feeling!
Like all things thyroid it's one big juggling act, welcome to the club.
I would take one thing at a time: First increase your T4 (levo) to a point where it is in the upper range. Measure your T3 to see if it increased. If it did not, measure your selenium level (this is the catalyst for the T4 to T3 conversion). If your selenium is low, this could be the reason for your low T3, so take a selenium supplement (I eat Brazil nuts - it's the easiest and safest way imho). Do this for about a month then measure your T3 and selenium levels. If your selenium is still low, increase you intake of selenium and repeat. If your T3 does not increase once your selenium is optimal then increase your T3 dose very very slightly - after about 2 weeks measure your T4, T3 again. If necessary increase your T3 again very very slightly and repeat.
If any of these experiments make you feel ill, drop back to your previous doses.
And don't overlook what Batty1 said - "Go with how you feel", if you feel good and your blood tests suggest otherwise, then ignore the blood tests.
btw, since you are in the US you can get blood tests via True Health Labs (an Internet service that works with your local blood draw lab) and I get my Brazil nuts (for Se) from nuts.com.
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There was a whole thread on here a couple of years ago discussing why FT4 drops when you take T3, and there were a lot of theories put forward, but none of the really held water. Personally, I just think the body excretes what it feels it doesn't need. 
Test results exactly the same despite increase in T4 
T4 Depletion, what's going on?
Increase in levo but free T3 going down? Recent bloods are baffling me. 
