T3 3day lag: Is this a thing? So, when you... - Thyroid UK

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T3 3day lag

Murphysmum profile image
41 Replies

Is this a thing?

So, when you initially start, it takes around 3 days to get into your system to be very non-scientific about it.

Does this lag still apply from then on? Or should you then have a ”level” in your system? Im thinking not because of the short half life.

I only ask as this could go al long way to explaining why I feel different on different days. Obviously there are lots of other factors which affect the action of thyroid hormones and levels in every cell of your body but I wonder if for example, though I’ve been tasing T3 for a while now, if I took 15mcg less on Saturday, would this have a knock on effect on Tuesday?

I have a feeling it’s really not going to be this simple but in theory?? 🤔

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Murphysmum profile image
Murphysmum
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41 Replies

I think there is always a lag for me, I start to feel the effects of t3 in the evening of day 3. It is not simple :( there are so many fluctuations, for me it is like a see-saw, mad fluctuations first few weeks and like literally anything can happen - wildy going from over to under symptoms, week 5 more balanced and mostly more hypo then lol :)

To answer in short: if you took less on Saturday, yes you can feel it on Tuesday, absolutely.

Murphysmum profile image
Murphysmum in reply to

Thankyou!

I always thought this was the case so wanted to confirm.

I’m trying to tie up dose with activity, with resting hr for the last couple of months.

It’s not easy!! I thought I was coping with the added exercise but now wondering if I’ve made myself crash as people warned.

Bloody determined I won’t have but something has kicked off my current horrible spell. Really honestly haven’t felt like this since before I started T3.

I will be genuinely gutted if I have to stop my couch to 5k. I’ve really enjoyed getting a bit fitter again and hoped doing it in moderation with other things would work.

I’ll keep looking at the notes to see if there’s a pattern!

in reply to Murphysmum

This might sound like a strange question, but have you ever taken your t3 dose all at once?

Murphysmum profile image
Murphysmum in reply to

Yes but I didn’t like it. Felt very anxious.

Worryingly, now if I take more than 15 mcg (certainly first thing) I get chest pains and feel like that. Not sure what’s going on there, think I might have pushed up my cortisol. Hope it goes back down again!

I was quite happy taking 20mcg in the morning until the last week or so 😢

in reply to Murphysmum

Okay you can't tolerate 20 now because you have reduced, that is normal, this goes away once you get used to it. Your adrenaline may be compensating for the lack of that 5 mcg t3 or your body is surprised you want to add it again and it is confused, not a scientific term at all.lol :)

When you dropped levo completely, have you tried taking all in one go?

If I split, I feel undermedicated and have strange symptoms all the time. So I was curious...

Murphysmum profile image
Murphysmum in reply to

Yeah, I totally get what you mean, and actually, you might have a point with the adrenaline and over compensating and all that! I think you could be onto something.

When I dropped levo did I try it? Umm, I can’t remember! My gut feeling is no, I think I would still have been on some levo when I tried it.

I think the not being able to tolerate 20 now might be as you say because my levels are low.

Agh! It’s all so frustrating. I’m going to have to give up my running for now and I was determined not to. But I can’t go on like this. I’m almost as low as I ever was. Slightly less tired, sleepy but I feel awful, really awful.

I’ve ordered a new blood test but I won’t be able to submit that until Monday at the earliest, so don’t know how much that will tell me. Hopefully it’ll show crazy low T3.

I keep thinking how good it would be if someone invented a quick blood test like diabetics have. You could totally nail it down. In the meantime tho.....

in reply to Murphysmum

Yeah, but it may not be like this, you could be getting temporary fluctuations from this drop and feel low for a while, this is completely normal, I have been through it a dozen times. But you need to persevere, wait at least two weeks for this to settle.

And post results, let's see what is happening then.

I have seen that when you take a smidge of levo or no levo, you need your ft3 reading quite high or even over range. Did you try to top up with 2.5 or 5 mcg t3? Sometimes 10 mcg increases are too big.

NWA6 profile image
NWA6 in reply to Murphysmum

Could it be something to do with the warmer months? I’m sure somebody here said something about some people needing less replacement during summer??

Murphysmum profile image
Murphysmum in reply to NWA6

Agreed. I don’t personally find that but then I’m still trying to pin down my ideal dose.

It’s definitely “a thing” tho 👍🏻

Pascha1 profile image
Pascha1 in reply to

My T3 instant and if i didn't top up several times in the day I start aching and feel sleepy and quite Hypothyroid I haven't left it a day without but just know lt wouldn't be good for me, what works for one may not be the same for another we all have different genetics I am a speedy tablet metaboliser ( shame that's not for my fat as well but its not ha ha

Murphysmum profile image
Murphysmum in reply to Pascha1

Well this is what I find confusing.

So there’s roughly a three day lag to begin with, but like you, I feel it wearing off during the day.

However, is that a lag until it reaches a level that becomes effective (to a point, dosage obvs comes into that ) and then you’re continually topping up each day?

I’m not sure exactly how it works but I think you’re right, we’re all different and have to find what works for us 😊

Pascha1 profile image
Pascha1 in reply to Murphysmum

are you on T3 mono or combi T4/T3 ?

Murphysmum profile image
Murphysmum in reply to Pascha1

Ha! well, I have been both.

At the moment I will still have some levo in my system but I haven’t taken any for a few weeks now.

I’ve written previously on here about combo or not. I found a huge difference dripping levo but then once it was out of my system I found my levels hard to maintain. I added a small bit back in again but tbh, I don’t think it helps. I think it blocks the action of the T3.

So I’ve dropped it again and intend to stay off it for the foreseeable and see if I can get my T3 consistent.

Pascha1 profile image
Pascha1 in reply to Murphysmum

T3 is an Active drug so pretty instant it activates after you swallow it it doesnt have to make it through a million enzymes to get to the liver to then convert in the liver sso there for T4 stays in blood a lot longer thats what prodrugs do.. T3 being active will enter body and be active and although stay in body a small time its not long so the peak won't be that long and then will start to leave the body slowly but I would feel dreadful if I didnt have it for 2 days as i can feel each dose as it runs out I start to ache etc , it doesnt stay in the body that long where as T4 is a prodrug which can stay in body for weeks

tattybogle profile image
tattybogle in reply to Pascha1

Murphysmum

I read something on here the other day about T3 staying in CELLS for 2/3 days once they are saturated with it . So i think there are two issues here ;

How long it lasts in the blood.

How quickly it is available to be used by cells because of not having to be converted fromT4 first.

How long it remains available to be used inside the cells once its in them.

Oh .... that's three, sorry.

As usual i cant remember where i read it now...sorry.

(And anyway i've decided all this searching for scientific reasons is silly and i'm going for a more sensible theory........... that actually my Adrenal and Thyroid Responses are controlled by those little Blue flying pixies that fly around the lampshade causing mischief in Harry Potter's classroom, and they are just throwing T3 and Adrenaline around my system at random and laughing at me trying to figure out what's going on.

I think this makes much more sense.) :)

Murphysmum profile image
Murphysmum in reply to tattybogle

I’m going to go with that theory as well! Much easier to follow 🤣🤣

Do you know, now you mention it I’m quite sure I’ve read this somewhere before too. I should have, there can’t be much that I haven’t read over the last three years!

It doesn’t make it any easier in practice though, does it?

So, I’m beginning to think (and what you’ve said works with this), that I’ve got T3 to a good level IN MY CELLS, felt well and begun to increase my activity levels. I’m thinking that since then, although I’ve been “topping it up” several times a day (v scientific 😂) the levels in my cells are have dropped. And now I’ve crashed, again.

Or something along those lines. I’ll go with the pixies....

Pascha1 profile image
Pascha1 in reply to Murphysmum

when you 1st took T3 how long was it till you noticed it working Murphysmum

Murphysmum profile image
Murphysmum in reply to Pascha1

I don’t disagree with that you say.

I found a difference on the start of day 3 when I first took T3. That said, I also feel a difference within a few a days of taking levo. This has happened so many times it’s not my imagination!

I was just curious how people found it worked for them. Whether you’re on a combo will make a difference and that’s something I will have to learn to balance out better if I remain on T3 only.

First I have to work my way back out of my current crash and I can say for sure at them moment that the increase I made 4 days ago has made no difference yet... so work that one out! 🙄😩

in reply to Murphysmum

on half life of t3. Just because it peaks fast in blood (this is the feeling of it working straightaway), or metabolising fast doesn't mean it doesn't have 2/3 days effect on cells. Once your dose builds up, the effect lasts, if you feel it running out, you are not on enough. I only feel the running out when I split the dose, it makes me feel uneven, I can crash, very hypo etc. When I take it all in one go in the morning, cells get saturated and it works for me for 3 days still after stopping.

Murphysmum profile image
Murphysmum in reply to

Interesting. I’ve recently split from 2x to 3x.

I do wonder if the smaller doses work. However, it was the sudden inability to tolerate the full 20mcg dose in the morning that made me split 3x.

🤔🤔🤔 confused.com!

in reply to Murphysmum

I had the same problems splitting, taking one dose all at once sorted that issue out. I had the same inability taking more that 15 t3 in the morning when splitting my t3 dose into 3, then into 2. Now I am up to 22.5. 4 years ago on NDT I was taking 150 mcg levo and 38 t3 all in one go.

Murphysmum profile image
Murphysmum in reply to

That interesting.

The most I tried in one go was 30mcg when I was taking a 50mcg daily dose. But that didn’t feel as uncomfortable as 20 does now! If that makes sense.

Once I get past this current crash I’ll try again. It’s only really now we’re having this chat I’m wondering whether the smaller doses aren’t a good idea. I mentioned Paul whatshisface’s wave theory in w previous post and I think it might be right. Ie, a bigger wave of t3 is needed to wet the whole rock on a shore... smaller waves, even giving a bigger final dose don’t work the same.

My endo also suggested splitting more often if I dropped levo which is again why I was trying it. I like her, she’s really good and definitely on my side but we know they’re not always right!I wonder how many others have gone onto T3 only and managed to take one or two doses, not regular splits?

More food for thought... and nothing really to do with lag!

in reply to Murphysmum

Absolutely, you can try again, just let it settle a bit now. I am also waiting for my dose to settle a little before a change because otherwise I will get this anxiety, palps and adrenaline rushes again and they are not pleasant!

Yes, I believe in saturation of cells. T3 really isn't that short acting like people think, of course it is shorter than silly levo, but for me it is a good thing as if I truly overdose then will see difference in 3 days starting to happen.

Don't want to speak for others, but I know Greygoose takes it all in one go in the morning, t3 only, and Shaws is the same. There are more people on here that do it.

Murphysmum profile image
Murphysmum in reply to

Yes, they’ve told me that before too.

Once I get on a settled dose again - tho lord knows what that actually looks like, more than 6/7 weeks without any symptoms would be good! - I may try and see if I can play around with bigger, single doses.

Thanks 😊

in reply to Murphysmum

I know, it would be nice, I am currently struggling with a whole body pain from water retention plus insomnia, I don't wish it on my worst enemy LOL hello from the Michelin Man!

Meanbeannyc profile image
Meanbeannyc in reply to

I am feeling the same today. No sleep, hurting, and swollen.

Meanbeannyc profile image
Meanbeannyc in reply to Murphysmum

My coworker does T3 only and only does 2 doses. She only takes 10mcg a day. Has no thyroid. And has a TSH of 2 with a high FT3. So weird. Weirder thing is that her TSH was 96 on 350mcg synthroid.

Pascha1 profile image
Pascha1 in reply to

the 1st T3 I had within 20 mins my so fibromyalgia went completely, everything looked like I had got colour so it got into my cells withing 20 mins, so again everyone is different, I actuaklly felt alive again and also I could walk better I was no longer stooped over all within 20 mins

in reply to Pascha1

Absolutely agree, I feel the same, but the biggest difference for me personally is after 3 days. T3 is such a lifesaver, on levo only some of us would be dropping like flies!

Murphysmum profile image
Murphysmum in reply to

Oh poor you! I hope that gets sorted out soon.

I was fine on levo for about 15 years. Well, I say fine, with hindsight I now know there were some issues and suspect others. However, I felt well within myself.

All of a sudden it stopped working, or I stopped converting.

Thank goodness for T3. I can’t imagine life without it now. It would be pretty much like the last few days for me, and I couldn’t stand that for long ☺️

in reply to Murphysmum

I hope so too! I was never really good on levo, unfortunately! Over a year ago I was a yoga teacher and doing PT with my trainer, cycling to and from work everyday, running 5k etc. even managed to get some pull ups, weight 63 kilos, now 79 kilos and so much water retention plus insomnia (hence why replying now), can't exercise at all. I am waiting for my t3 to stabilise a little now before I drop levo and increase t3.

Meanbeannyc profile image
Meanbeannyc in reply to

You were having swelling and insomnia on T4 only?

in reply to Meanbeannyc

On T4 only and T3 T4 with higher t4 dose, I am reducing T4 and increasing T3

Meanbeannyc profile image
Meanbeannyc in reply to

You had insomnia on the higher t4 dose and no T3? I just want to go to sleep

in reply to Meanbeannyc

Yeah, my body needs more t3 than t4, I sleep 6-7 hours a night now, but used to sleep 3 maybe.

Meanbeannyc profile image
Meanbeannyc in reply to

Maybe Bc half life is so short? That’s why u sleep better on T3

in reply to Meanbeannyc

Maybe, but t3 gets stable in your blood if you take it everyday, it doesn't dissappear after few hours

Meanbeannyc profile image
Meanbeannyc in reply to

But it does in a few days, yeah?

in reply to Meanbeannyc

If you stopped taking it, then yes, 1 day from blood, about up to 3 days from cells, but that is just my experience.

Meanbeannyc profile image
Meanbeannyc in reply to

Makes sense. I’m trying to figure out why you’d sleep better with the lower T4/higher t3

Meanbeannyc profile image
Meanbeannyc in reply to Pascha1

Stooped over?

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