If ft4 is 80% in range and ft3 75% in range could it help you feel better to swap some t4 for more t3 or is that pointless?
If levels are good can it make you feel better ... - Thyroid UK
If levels are good can it make you feel better to swap some t4 for some t3?
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Sallyn
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You'd have to try it to find out. It might make things better, it might not.
How long might it take after starting to add T3 to know if it is effective?
Impossible to answer that question. Some people find a difference instantly. For others it takes a while. We're all different.
That's a good answer, let's me remain open and not in a hurry to feel results. Thanks.
I'd add to Greygoose's answer that to really really know whether T3 is helping and suits you, you need to stay on it for a decent long trial. This includes adjusting your dose a few times until the blood tests look as good as you can get them (there's no point deciding it doesn't work if you're very undermedicated for the whole trial).
This needs to be at least a few months, maybe 6 months to really be sure whether you've had improvement.
But I would expect you to get some improvement within a few weeks or a month, and if you you're lucky you'll feel some difference in a few days.
Pay a lot of attention to how you feel, how much you can do, how frequently symptoms come up. If you're quite able you may need to do some exercise, some hard puzzles, or stay up late or whatever to test your limits!
Yes, still loosing a lot of hair, palitations, tired. Have now been 1,5 weeks on lower dose levo and increased T3 to 18.75 3 days ago. I feel very tired until I take 2nd dose at 2 pm. Would this indicate that I might be better of taking the whole dose at once in the morning?
Once again, that's a very individual thing. You'd have to try it to find out if you feel better taking it all at once. But, it's still very early days, and you have to give things time to work. 1.5 weeks is nothing in thyroid terms. Your body is still getting over being deprived of T3, and suddenly having it available again. So, if I were you, I would give it a bit more time taking it the same way, before changing.
Ok, do you think it's wiser to stay at this ratio of t3 and t4 for a couple of weeks before swapping some more t4 for t3? How much t3 do I add for every 25 t4 i decrease?
T3 is very very short acting in the body. This is why many people who take T3 find they need to divide their doses into am and pm, or sometimes even more. If they don't, they feel a crash and fatigue second half of the day.
I started with T4 and instantly felt better, like in 2 days, but knew I needed T3. Day 3 I added 5 mcg T3. It immediately helped, but I could tell it was not enough. Day 3 of being on T3, I added a second 5 mcg, or 10 total. This increase was under the instruction of a physician. It immediately helped. I continued on that dose for over a year and then added a 3rd 5 mcg in the pm. That continued for years. My levels are now optimal and stabilized, I feel great, and I have found I don't have to take that 3rd pm T3 all of the time. Eventually when I did, my FT3 got a little higher than I'd personally like it to be 4.0 (2.3-4.2).
T3 is very very short acting in the body.
No it's not. It stays in the blood for about 24 hours, but the T3 that has been absorbed into the cells continues to act for three or four days.
Yes, it actually is, believe it or not. I'm not making this up! 
T3 has always been short acting, and T4 has always been long acting. The peak therapeutic effect of T3 is 2-3 days, while the peak therapeutic effect of T4 is 4-6 weeks. Then there is the biological half-life. The biological half-life of T3 is about 1 to <2 days, compared to T4 that has a half-life of 9-10 days in hypothyroidism. Half-life is the time it takes for plasma concentration of drug to reduce to half of it’s original value.
So, as soon as you take 5 mcg T3, it’s full availability is immediately being reduced. That 5 mcg will be reduced to just 2.5 mcg concentration in your plasma as soon as 1 day, or up to 2 ½ days. This is why some people with very low FT3 levels who only take their T3 experience a crash as the day wears on, and particularly in the pm. And this is why many people taking T3 find that they feel their best when breaking their dosage up into two or more administrations. In comparison, T4 is long acting. It takes 9-10 days (in hypothyroidism, 3-4 days in hyperthyroidism) to reach half it’s original value in serum plasma concentration.
Regarding peak therapeutic effects, the maximum pharmacological response to T3 occurs in 2 or 3 days. This means that whatever dosage a person is taking, they will experience maximum benefit in 2 to 3 days. In contrast, it takes 4-6 weeks for the maximum pharmacological response to T4 to occur.
Depending upon a person’s FT3 blood results and their response to 5 mcg T3, increase in dosage can occur within days (under a physicians care), or by the end of week one. It’s not going to get any better than whatever the response that they’re experiencing at 2-3 days out.
If not responding positively to the current dose, it makes not sense to continue for weeks, hoping it will change. The same principle applies for T4 supplementation. If symptoms persist, then the dosage isn't correct.
Well, it does depend on your definition of 'short'. Obviously it's around for less time than the T4. But, the way you explained it, it sounded as if it was all gone in a couple of hours.
Can you give the link to the site you copied and pasted from, there, please?
Copied and pasted??? How insulting. I didn't copy and paste it from anywhere. I already knew this information due to education. Besides, I personally have Hashimoto's and am very familiar with the medications myself. I take both T3 and T4 don't take medications unless I am educated about them.
Anyone taking T3 and or T4 should be fully knowledgeable about the ins and outs of these medications, and especially those on the internet dishing advice. Sadly, I see that is not the case. You need to check your references. Take the time to research and fully understand the medications and vitamins you discuss, not just pasting some link.
Well, now whose being insulting? What you said above is more or less what I said. But, you just had to try and correct me, didn't you. Now you're calling me ignorant? You're not saying anything I didn't already know, above.
People don't normally go into so much detail - usually unnecessary - when answering a simple question. That's why it looked like it was copied and pasted from somewhere. My mistake! But no need to get offensive.
It's okay. Everyone on this board is human. I appreciate your humble response. Thanks!
Totally agree with greygoose. This is where it becomes a trial and error process....finding what med or combination works best for you. I don't think there is any quick way to find out sadly. The thing is if you change one thing at a time if it doesn't work or you feel worse you can change back.
Blood tests tell you what is in the blood stream not what is in the cells.....so for example I found certain ndts dont work well for me probably due to certain fillers......thats my individual quirk. Whether it inhibits uptake in my cells have no idea.....my blood tests are simular....but I feel very different.....so why? No one knows really....
There still much to discover about the thyroid & how it works, what works & why people have such different needs in treatment.
Are there any areas of your health you feel need improving? If you are unable to keep weight down for instance. If you aren't sleeping well. Is your hair falling out? If everything is copasetic, you should probably not make changes. Your pituitary gland and your adrenal glands are also involved in your use of thyroid hormones. Perhaps supporting your adrenals would make more of a difference.
Yes, still loosing a lot of hair, palitations, tired. Have now been 1,5 weeks on lower dose levo and increased T3 to 18.75 3 days ago. I feel very tired until I take 2nd dose at 2 pm. Would this indicate that I might be better of taking the whole dose at once in the morning?
Sally, I looked at a few of your posts and I'll be honest I do not like T4 but what I noticed is that usually when people start taking T3 the test for T4 goes down and yours didn't. Do you realize that your adrenals will make reverse T3 out of T4 if you have too much in your system? That may be where your symptoms are coming from. Let me know if I misunderstood that you did not reduce T4 at the time you added T3.
I've done all three and preferred some T3 with my NDT but have just switched to T3 only because it is easier to get. I take two tablets together at night but I've done it other ways as well. I'm kind of guessing that adrenals may be stressed when having to make reverse T3 from excess T4. I like T3 because not much conversion is necessary and seems easier to assimilate. Again, that is how it seems for me. Dr. Lowe advocated taking all T3 at one time rather than split doses. I realize that is controversial so I would try both and see what happens.
Totally agree with Greygoose, these things are trial and error, suck it and see.
Although I would add the question, do you feel unwell now?
That will determine how desperate you are to try it. If you're very well you might want to wait till a time when you've got plenty of time to rest, as you might feel weird at first. Although you may find you thought you were well, but have learned to put up with a lot, and feel even better with T3. If you still feel unwell, it's the next step to try.
Unfortunately you will almost certainly have to self medicate and buy your own.
Yes, still loosing a lot of hair, palitations, tired. Have now been 1,5 weeks on lower dose levo and increased T3 to 18.75 3 days ago. I feel very tired until I take 2nd dose at 2 pm. Would this indicate that I might be better of taking the whole dose at once in the morning?
I suggested to a friend that she should add some T3 to her Synthroid but her doctor only increased her T4. Her hair started falling out. Her doctor said that was the trade off. This was to help shift some weight. She decided to keep her hair and reduce T4.
Hi Sallyn, I'm a bit confused because I thought you were asking whether you should try T3. But sounds like you're already taking some T3 and your new question is about what time of day you should take it?
Could you give us a bit more information on your illness, what doses you've tried, and any thyroid blood test? I'll go back and look at your past posts to see if I can't piece anything together, and write some more.
Hi Sallyn, have had a look back and you've given a lot of information, and its a complex story. I don't have time to look at it all right now.
Could you reply to this message so I will get an email notification, and will remember to come back and write you a post later!
I didn't reduce t4 when I started to add t3 but now when I came to 18.75 t3 I reduced t4 from 112.5 to 100. Do you think I should swap some more? Latest results was
Ft4 20 (12-22)
Ft3 5.8 (3.1-6.8)
So how much t4 would you think I can swap for t3?
Was you t4 lower before? If not I would reduce that.
I went gluten free this year and since then it has been in the 20's. Before that it has ranged from 17,5-19,8. so the latest results was before decreasing t4 by 12.5. Do you still think I should reduce it further? If so I think I need to add more t3 as I am feeling very tired before my 2nd dose as it is now.
I know it seems counterproductive but your FT4 shouldn't be that high when you add T3. Your FT3 is good. Actually both are good so you should be feeling good but since you aren't I think you might feel better without so much T4 especially if it's becoming reverse. Sometimes it does help to know the RT3 result as well because you see the ratio between free and reverse. Taking 100 T4 with 18.75 T3 or even 25 T3 is an average dose but again, why is your FT4 so high. I think if it's only been a few days on that dose just stay with it for now and let your body accustom itself to more T3 which may even make the T4 work better. You could consider taking them all together.
Sometimes people find they need to reduce their dose after going gluten free. It sounds like your body is processing T4 a bit better, and getting more benefit from the tablets. Even more reason to reduce it a little.
Perfect, now I see what you mean. Yes, generally when adding some T3 you would a corresponding amount of T4, as they are both the same kind of hormone, just in different forms (a bit like if you had some frozen peas and some fresh peas - they both add up to more peas). The only time when you might not reduce the T4 is if you are already underdosed.
At the moment you're quite near the top of the range for both, so I would definitely reduce some T4 when you add T3. T3 is about 4x as potent as T4, so if you add 10mcg of T3, reduce 40mcg of T4. It's okay to round up or down for the sizes of tablet you gave, as these equivalencies are quite fuzzy.
High freeT4 doesn't really do any good, and may do some bad, so you might even want to reduce it a little more.
If you're more energetic after your first dose, and then more tired later in the day, you can juggle the dose a bit to get it more even. I take 3 doses and try to get my energy levels equal through the day, but it's never quite right. Ok always either exhausted by late afternoon, or just getting going when I need to go to bed
So for example, I currently take 3 grain in the morning, 2 after lunch, and 2 at night (this is a very high dose). I used to do 3, 3, 1, but I found I was getting weepy and nauseous in the evening, so when I noticed the pattern I switched it round a bit.
Hi Sallyn, I've gone back through and read all your posts. It's not quite as complex as I thought, but I think maybe you've recently changed things a bit fast.
In your first post you had 3 sets of results, all with Levo at 125mcg, then with 3 different doses of T3. Your freeT3 rose each time, and freeT4 rose a little, too. By the third dose your results looked fine but you felt over medicated.
One thing I noticed on that post was that some of the blood tests were taken after 4 weeks. Best practice is to wait 6 weeks, and you can get some strange results before that. So it's possible these aren't completely reliable.
So you reduced back to dose number 2, which I think was 125mcg Levo, and 12.5mcg T3. But the overmedicated feeling took ages to go away. I think you may have then reduced the dose to 112 Levo and 12.5 T3. Then I saw a blood test with that result? Healthunlocked isn't very clear on the dates, but this must have been well under a month stable in that dose.
I see in this thread that you've upped your T3 back up to 18.75, and dropped the Levo to 100? And there seems to be a new blood test. Does that go with this dosage? Ft4 20 (12-22), Ft3 5.8 (3.1-6.8).
Now according to Healthunlocked a load of these changes have happened in about a month. You've been on 3 different doses in the time you've been posting on the forum. So the most important thing is to stop chopping and changing doses. You must stay on the same dose for long enough for your body to settle down. Before that point you can't tell whether you're overmedicated or undermedicated or anything else.
Choose one change to make at a time. Change your dose by equiv of about 25mcg of Levo. Stick with that for 6 weeks, and then get a blood test. Blood tests won't be accurate if you do any different, as your body is still changing. It actually takes months to really get used to a new dose.
I think the most useful clue you've had this whole time is that you've felt overmedicated. This is very useful, because as you try to close in on your ideal dose, it tells you your best dose is probably just below where you were then. So you can work backwards and try to find the sweet spot.
I think you're right to be thinking it was the high T4 that was causing the over medication, and you'd probably be better off with a higher T3 dose, and a lower Levo.
If you're currently taking 100 Levo and 18.75 of T3, I think that's a reasonable dose to stick with. If we compare it to the dose you felt over medicated on, 125 of Levo and 18.75 of T3, it's a reduction of 25mcg of Levo, which is a nice, sensible, small decrease. Now all you need to do his stay on that for 6 weeks, get a blood test, and see how you feel.
I think you may have increased a bit fast before, and that's a recipe to get overmedicated, because you rush past your dose before your body has had a chance to catch up. Once it does catch up, you start to feel overmedicated.
It might be worth getting a set of vitamin tests as well, to confirm they're still good. Folate, ferritin, vit D and vit B12 are the main ones to get.
Well put Silver Advocado. I well remember doing something simular, increasing/chamging my doses too quickly. It always confuses the picture. Its frustratingly slow the medication changes to find your sweet spot but the only way to be sucessful.
The good news is that when you do finally find your sweet spot you can settle doen into minor tweaks due to weather variations!! Ive been on the same dose for 6 years now, albeit a tadge more or less according to weather extremes.
Keeping a careful log of my medication doses, supplements taken, before rising pulse & temp, plus short notes on how I feel, alongside blood test results slotted into my log really helped me. I could look back over the log to spot patterns. Tedious but well worth it.
I dont keep a log now as am stable but I would reinstate it if ever the need arose.
Hi Sallyn. Have you been tested for Hashimoto's? TPO/ab and TG/ab the antibody tests.
Here is an explanation of how and why T3 supplementation is fast acting, while T4 is slow acting. T3 has always been short acting, and T4 has always been long acting. The peak therapeutic effect of T3 is 2-3 days, while the peak therapeutic effect of T4 is 4-6 weeks. Then there is the biological half-life. The biological half-life of T3 is about 1 to <2 days, compared to T4 that has a half-life of 9-10 days in hypothyroidism. Half-life is the time it takes for plasma concentration of drug to reduce to half of it’s original value).
So, as soon as you take 5 mcg T3, it’s full availability is immediately being reduced. That 5 mcg will be reduced to just 2.5 mcg concentration in your plasma as soon as 1 day, or up to 2 ½ days. This is why some people with very low FT3 levels who only take their T3 experience a crash as the day wears on, and particularly in the pm. And this is why many people taking T3 find that they feel their best when breaking their dosage up into two or more administrations. In comparison, T4 is long acting. It takes 9-10 days (in hypothyroidism, 3-4 days in hyperthyroidism) to reach half it’s original value in serum plasma concentration.
Regarding peak therapeutic effects, the maximum pharmacological response to T3 occurs in 2 or 3 days. This means that whatever dosage a person is taking, they will experience maximum benefit in 2 to 3 days. In contrast, it takes 4-6 weeks for the maximum pharmacological response to T4 to occur.
Depending upon a person’s FT3 blood results and their response to 5 mcg T3, increase in dosage can occur within days (under a physicians care), or by the end of week one. It’s not going to get any better than whatever the response that they’re experiencing at 2-3 days out.
If not responding positively to the current dose, it makes not sense to continue for weeks, hoping it will change. The same principle applies for T4 supplementation. If symptoms persist, then the dosage isn't correct.
It would be advisable to lower the T4 before adding some T3 . So that you don't experience hyper issues . Going slow and low is another great advice . There are times that some who start on T3 can unmask some adrenal insufficiencies . Having nutrients in place is very helpful . Vitamin D , B-12/folate Iron if labs show low range . SeasideSusie has EXCELLENT information's with the nutrients that are so very helpful with our thyroid meds .
SlowDragon has GREAT Information's with gluten free diet .
Best Wishes on your next steps .
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