I’m on 50mcg T4, 30mcg T3. Recent bloods came back as FT4 10.9 (12-22) and FT3 6.4 (3.1-6.8). My doctor isn’t concerned about T4 as it’s inactive and prefers to prescribe T3. The T4 I take was a compromise. I’ve read on here that T4 does seem to have its own effects and I’m wondering if anyone could tell me more about that. I feel fine but my periods stopped abruptly when I got to 6.8 and haven’t returned since. Of course this could be my age but I’m wondering about it.
Thanks for any help.
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Jasma
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What an enlightened doctor! You can't be in the UK
He's right that T4 is a storage hormone, that converts into T3, the active thyroid hormone. UK doctors look more at T4 because (a) they understand it better; (b) it's much easier to monitor, because it has a much longer half-life than T3, which fluctuates very dramatically over the course of a day; and (c) T4 meds are sooooo much cheaper. But it's free T3 that your body needs, and you have lots of that!
I assume your blood results were taken with a 24 hour gap from taking T4 meds and 12 hours from taking T3 meds, otherwise you will have a false reading. Do you split your T3 dose?
And feeling fine and no periods sounds pretty good too
Some people are fine with low Ft4 when taking mix of levothyroxine plus T3
Others find low Ft4 causes symptoms, despite high Ft3
To find out if you might feel, better with higher Ft4 you could trial a 25mcg increase in levothyroxine ....but you would probably need to reduce T3 by 5mcg
I'm one of those people who needs T4 to be optimal, as well. When I added T4 to my NDT, it changed my life. I could never get my T4 up with NDT alone. I found the info that helped on a website called The Tired Thyroid. I also got the author's book. You could check those out & see if they help you. I found my hair & eyebrows really need T4, as well as my energy level. I couldn't get optimal FT3 or FT4 from T4 or NDT alone.
From my own experience having low T4 with high T3 I felt very spacey lethargic brain fog . I had to read something several times to understand what I was reading.
With the thyroid journey we have to try and see which way works the best for us. It's trial and error and it's not one size fits all.
If the dose of T4 feels high for you journal your symptoms . Symptoms are very telling . and are cellular results. With T4 dose that is high for me personally but for everyone it might be other symptoms .From high T4 for me I get headaches , palpitations, aches/pains, sweating , insomnia, hungry all the time, fatigue, moodiness, anxiety, irremediable, heat/cold intolerant, itching and skin breakouts, thirsty.
Lowering slowly the T4 to a comfortable state and not to over shoot the *optimal*dose and allowing time for the body to acclimate to each small dose change. Prior to introducing *any* T3/NDT . Running lab with FT4 , FT3, TSH is helpful to see if the symptoms and labs confirm how we feel .
When introducing any T3/NDT with T4 start with a very minute dose and to split it and see how it feels before increasing any more T3/NDT .
In addition nutrients are very important they help with our thyroid meds to work better for us . Vitamin "D"/K2, B-Complex , B-12/folate, Iron if you test low, Vitamin "C", magnesium, Celtic Sea Salt for adrenals/electrolytes.
Don't Give Up . Keep Working it . You Will Get There.
Thanks jgelliss, similar for me, with high for me t4 I get sweating, heat intolerance, then cold spells, insomnia (but I get that with undermedication too), anxiety etc. So far I have established that I need my t4 around 40%.
The best is to trust your gut instincts and to do what feels right to you. Your are ultimately the *Best* judge of what thyroid meds works best for *You*. No one else.
Trust Yourself and you will find your *Optimal Dose*.
It's better to take mostly L-T4 if you can get better on it (some patients can't). This is because some organs such as the brain take in mostly T4 and convert it locally to T3, this allows for local regulation of T3 levels. In some patients this conversion is impaired so they have to take T3 which is not ideal. I would be inclined to take 100 mcg L-T4 and 10 mcg L-T3 in split doses (2 x 5 mcg) and see if that works.
Although T3 is the active hormone I believe where the T3 is coming from matters. In healthy people much T3 is converted from T4 in organs that have a degree of local regulation. Thus, it's preferable to avoid bypassing this mechanism if possible.
Thank you jimh111. That’s what I was looking for. I’ve been googling and found a few references to that effect.
Hey Jasma, there are studies indicating that t4 has its own purpose, a lot of people disagree with it, but I know that I don't feel with low t4, also don't feel well with high t4. It is not a bad idea to try to increase levo and decrease t3, but I would go with max 25 mcg increase (t4), 5 mcg decrease (t3), otherwise you may experience some weird symptoms.
No worries Jasma, I recall that you said you have never been on higher levo and were put on t3 straightaway, so it is definitely worth a try. Best of luck!
That’s right. I was only ever on a starter dose of 25mcg Levo alone. I’ve thankfully never felt really bad anyway so obviously when I’m asked I say I feel fine. At the beginning when my T3 was low-normal I had carpal tunnel, hair loss, spotting and fatigue but thankfully that’s all sorted now and the rest just seems a bit vague, hard to discern if it’s normal or thyroid-related.
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Reduce T4 by how much…?
Advice on T3/T4 combo bloods
Does thyroxine alone control T4 levels?
