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Thyroid UK
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Help with T4 & T3 dosages

I recently reduced my Levoxyl of 200mcg down to 175 due to not feeling well on that high of dose, it gave me high blood pressure and anxiety and my RT3 was on the high end according to last labs. I am also taking cytomel, I was on 15mcg but I seem to keep needing to add more. I am now up to 30mcg of t3. How do you typically know how high to go, I mostly go by symptoms and heart rate.

Before I went back on Levoxyl, I was on a trial of 150mcg of Tirosint and 15 of t3 but I felt the T4 was not enough so I switched back over to Levoxy atl 200mcg. Should I have just added more t3 instead. I am kind of messed up and need some guidance. My Endo is pretty much useless when I need her help and I'm so sick of hearing her say how more than 15mcg of cytomel is hard on the heart.

I also have to cut out the strenuous exercises that just makes my thyroid levels go haywire.

Thanks

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Exercising before we're on an optimum dose of thyroid hormones, depletes it and can give us unpleasant symptoms. I would look on T4 as an inactive hormone which has to convert to T3 and it is T3 which enables our metabolism to work normally.Sometimes levo doesn't convert effectively to T3.

I take T3 only and have had no problems with heart. In fact on levothyroxine alone I was forever in and out of A&E due to severe palps and even the cardiologist was puzzled. If people have thyroid hormone resistance they have to take large doses of T3 to eliminate their symptoms.

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Exercise was hard for me even when I was on an optimal dose. I read others have a hard time exercising and recovering as well maybe it’s something else?

I probably don’t have any thyroid tissue left after rai 20 years ago and that’s why I need a higher dose of t4? I know my body converts some t3 but not a lot.

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Research has shown that those not doing so well on levo improve on a combination of T4/T3 and I've read that a combination of 3:1 or 4:1 improves their symptoms.

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I’ve added t3 to my Levo about 3 years or so ago but have not been able to figure out the best combination yet. What would 3:1 or 4:1 be for example. I’m not familiar with that. Thanks

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Forget ratios. They are for healthy people with not thyroid problems. A hypo needs what he needs, and if that doesn't fit into any accepted ratio, too bad. After all, you couldn't get a worse ration that T4 only, that's no ratio at all!

When you add T3 to so levo, you start low and work up slowly - as with all hormones. Usually 5 or 6.25 mcg depending on the size of your pill. And, you increase by that amount every two weeks until you feel well. You don't have to decide what dose you're going to end up taking before you ever start - how could you possibly know. When you have enough T3 in your system, you will feel well, and you stop increasing. But, it's got nothing to do with ratios. :)

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Hi Grey, I started off with 5mcg of t3 around 3 years ago and recently have been somewhat steady on 15 of t3 and now I’m up to 30 right now. I hope I didn’t go up to fast. What’s the best way to divide doses of t3 to your t4 if your taking 30 of t3.

I always also thought that your body needs what it needs as far as thyroid meds go and never considered ratios to be a factor in dosing. Thanks

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Well, the 3:1 and 4:1 that shaws suggested are ratios. :)

The best way to divide a dose is the way that suits you. Everyone is different. Some people take it all together, at the same time, in the morning, or in the evening. Some people split the T3 taking half in the morning with their levo, and half in the evening before bed. You need to find out what makes you feel best. But, remember, for maximum absorption, T3 - like T4 - should be taken on an empty stomach, and hour before eating, etc. :)

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I thought t3 could be taken with food?

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That's what a lot of people think. But, comparing doses with results on here show a different story.

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I will take my t3 without food from now on. Hopefully I won’t need as much t3.

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Exactly. And you will also get a more consistant dose, because thyroid hormone reacts differently to different food. I'm sure you don't always eat exactly the same thing, in the same quantities. :)

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Thanks for the tip!

Why do endos not like t3. My endo scares me when I need to take more t3. She has told me many times to much t3 is hard on the heart. Why does the human body make it if it’s so hard on the heart?

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The problem I've found with a lot of people, not just endos, is that they cannot tell the difference between too much and just enough. When I was in hospital with suspected heart problems (I don't have heart problems!) they put me on a salt-free diet. I protested, and asked what the hell??? The specialist said to me, well, people tend to eat too much salt, so we've cut it out completely. Where the hell is the sense in that? Is that logical?

Of course too much T3 would be hard on your heart, but who says you're taking too much? We do need some - more than they think, actually. So, if your heart isn't showing signs of stress, you should be ok - not enough T3 is far worse. But, they don't learn about T3 in med school, so they feel out of their depth and prefer not to deal with it at all. it really all or nothing with them!

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Also if I was taking too much t3 the symptoms would show up like fast heart rate, anxiety, sweating and shaky hands. When I was hyperthyroid before they killed most of my thyroid my endo told me to put out my hand and I could see it shaking.

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If I’m on 30mcg of cytomel total for the day, would taking 15 in the morning with Levo be to much. I take 10 in the morning right now with Levo and I seem to need more t3 2 1/2 hours later. 15, 10,and 5 i was thinking?

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That's a very individual question, and unanswerable by someone else. Only you know your body.

Myself, I take 75 mcg T3 only, all at once, in the morning. It suits me, and I would hate to have to split it. Splitting it didn't give me anyway advantages, anyway. You will have to experiment to find out what works for you. Maybe you will feel over-stimulated if you take 15 in the morning, but maybe you'll feel better. Impossible to say in advance. Try it - it won't be dangerous - and see how it goes. :)

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I will have to experiment with it. My endo said Mornings are when most need most of their t3. I’m surprised taking your t3 all at once doesn’t bother you.

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At one point, I was taking 225 mcg T3 all in one go, and taking it at night. It didn't bother me in the least. T3 doesn't give you a the high that doctors like to imagine. :)

But, actually, taking your hormone at night is more natural. That's when your T3 is naturally at its highest. All the body's repair and regrowth happens during the night, and that's when it needs T3 the most. And, a lot of people find that taking it at night - or during the night - sets them up very well for the day. But, what would an endo know about that! lol

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I had no idea t3 peaks at night. I read somewhere that lower tsh inhibits t4 conversion. I thought lower tsh means more thyroid hormones.

When I was on 200 Levoxyl and feeling very anxious and overmedicated I lowers my levo and was able to go one day without cytomel and felt after I took my 175 that morning of Levo that my body was converting but then the next day I started crashing. I wish I could convert and keep hoping I will find some way to fix It. There are some natural doctor sites that say you need zinc, selenium and some other nutrients to convert. Have you explored fixing your conversion.

I wish I could have new thyroid tissue regrown....lol

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Low TSH doesn't inhibit conversion, I don't think, but it doesn't promote it, either. Even so, some people with low TSH manage to convert ok.

Conversion is very complicated. Of course, you do need all your nutrients optimal for all sorts of reasons. But that does not guarantee that you will improve your conversion. All sorts of things can affect it.

Myself, I don't have a conversion problem. I just cannot tolerate T4. Neither synthetic T4, and even worse the T4 in NDT. For some reason - I don't know why - taking T4 makes me very ill. But, I try and keep my nutrients optimal, anyway.

Anxiety can also be a hypo symptom. And if you weren't converting your levo, then it was probably that that was causing the anxiety.

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I’ve experienced anxiety from being hypo lots of times when my body all of a sudden wouldn’t covert Levo anymore and my genius doctors kept telling me my t3 levels are fine even though they were barley over the low normal range. One doctor told me t3 fluctuates throughout the day so it’s irrelevant.

Maybe it’s jist a pipe dream trying to fix my conversion issues. That’s weird how you don’t do well on t4. I hear some say they can’t tolerate taking t3 only and I would think there is a reason for t4 in the body besides conversion but I’m no scientist.

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Go to page 80 on the following link to read about T4/T3 combination.

tpauk.com/images/docs/reduc...

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Thanks shaw’s, I will check it out.

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I have been on T3-only and T3+T4. I have used the T4-only full-replacement dose (1.5-1.7 mcg/kg body weight) to compute a T4-only dose, then used the T3 power factor (1mcg T3 = 3-4mcg T4) to reduce T4 dosage and add in T3, similar to what Ridha Arem details in his book. Currently, I weigh about 78kg and am on a T3+T4 dose of 12.5+100, i.e. T3:T4 ratio of 1:8. Some do better on a T3:T4 ratio of 1:4, the NDT ratio; and there are a few who only do well on T3-only. If you want examples of computing a T3+T4 dose, you should find several under the list of all my postings. When I was on T3-only, I used five 12.5mcg doses of T3 each day, which worked out to about 0.82mcg/kg body weight. Yes, your endo's rule of never taking more than 15mcg T3 is ridiculous; my favorite example of that is that the late John C. Lowe used a T3-only dose of 150mcg every day, and he did not die of heart problems.

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I’m not familiar with ratios I’ve always just dosed until symptoms are good and watched my heart rate for to much t3. Sounds like you are really knowledgeable with t4 & t3 combination treatment. I’m trying to figure out how much t3 my body is going to need.

What would be the right ratio for me I’m wondering? Thanks

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I agree, symptoms are the most important thing in treatment. But I like to establish a dose partially based on logic, because I've been thru too many endos/GPs for whom dosing is just a WAG! When I've reached a 'sweet spot', I like to test FT3 & FT4 are so if I run into a rough spot later, I can check those and if they are where they should be, then I know the problem is elsewhere.

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I’m still waiting for my sweet spot.

What does the 1:4 ratio mean. I know from experience when I tried NDT I did not like the high t3 in it. Plus a pigs thyroid has more t3 in it than the human thyroid so it’s not really identical.

Have you found any supplements that have helped with conversion and well being. I know 20% or so of t4 is converted in the stomach and have tried to improve my gut bacteria. Thanks

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I use a boatload of supplements. B complex, trace minerals, D3 are those most important for thyroid. I had gluten enteropathy, so I use 12-strain kefir (as a probiotic) and free essential amino acids (plus a couple others) to deal with (permanent?) damage caused by gluten. I have used lab tests to make sure my FT3 is about 75% up in its range (2.77-5.27 pg/ml for my lab), tested in the morning before I take my dose for the day. I dose T4 at a level that puts my FT4 within the normal range, but I find that trying to push FT4 higher than about 1/4 up within its range, causes anxiety; so I let FT4 stay somewhat low within its range.

My hypothyroidism was accompanied by hypoproteinemia (due to digestive deficit caused by gluten damage), and one of the problems I had for a long time, was figuring out which symptoms were due to each of these. After getting thyroid mostly fixed, I found that pushing my Total Blood Protein up with amino acids, fixed both middle insomnia (amino acids seem to quiet my adrenals), and degeneration of muscles & connective tissue which manifested primarily as lower back pain/instability.

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I was on a b-complex but had to stop I was getting heart palps. Now I just take b12 and folate and I’m fine . Vitamin d gave me heart palps before to.

I thought having FT4 in the top range was ideal to but it also gave me anxiety and high blood pressure. Since I lowered it to 175 from 200 I’m fine now. My t3 dose is falling in the 20 to 25mcg range.

Your Gluten damage sounds like it did a number on you. So you just upped your food protein and it made a huge difference. Funny how nutrition plays a huge role in our wellbeing something doctors need to learn more about.

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