Please can you advise me on my calculations to ... - Thyroid UK

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Please can you advise me on my calculations to switch NDT to Levo

Gillybean1 profile image
10 Replies

If I currently take NDT 1 grain in split doses 7.30am and 3.30pm , do I take 100 mcg of Levo in one dose or split it? and do I also need to add 5 - 10 mcg of T3 to match the NDT content in 1 grain?

Is a switch over done immediately like for like? Or do I have to leave a day for the NDT's T3 content to drop back?

I am doing this as cost for NDT will be an issue for me soon ,and after 6 years trying various combos of NDT/T3 is still have not found my sweet spot, far from it. SeasideSusie mentioned I may find it easier to calibrate Levo and T3 more accurately, provided I can find a Levo thats agreeable.

Hoping you can advise, end of tether is how I really feel.

Every best wish , thank you G

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SlowDragon profile image
SlowDragonAdministrator

Try splitting your levothyroxine…..half waking and half at bedtime

Retest in 6-8 weeks

If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test

Similarly if normally splitting your levothyroxine, take whole daily dose 24 hours before test

If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal

Gillybean1 profile image
Gillybean1 in reply toSlowDragon

Many thanks SlowDragon for your reply. Just not clear whether 1grain NDT is equal to 100mcg synthetic Levo...? Or is 1 grain NDT equal to 38mcg synthetic Levo and 9mcg of synthetic T3..?

Every best wish, G

SeasideSusie profile image
SeasideSusieRemembering

Gillybean 1

If I currently take NDT 1 grain in split doses 7.30am and 3.30pm , do I take 100 mcg of Levo in one dose or split it? and do I also need to add 5 - 10 mcg of T3 to match the NDT content in 1 grain?

If you want to replicate the same amount of T4 and T3 as there is in one grain NDT, then that one grain contains 38mcg T4 and 9mcg T3. Whether you take your synthetic tT4/T3 all at once or split it really is down to experimenting and seeing how you get on.

When you do thyroid tests you take last dose of Levo 24 hours before the test and for T3 you split the dose the day before and take last part of your dose 8-12 hors before the test.

Gillybean1 I made a typo regarding the amount of T4 in one grain of NDT which I have corrected now.

Gillybean1 profile image
Gillybean1 in reply toSeasideSusie

Hello SeasideSusie,

Very nice to hear from you ,thank you.

This is the bit I dont understand, probably foggy-undermedicated numpty. On my pot of Armour it says 1 grain incl. levothyroxine T4 38mcg and liothyronine T3 9mcg. So does that mean I would need with synthetic Levo to take 38mcg (combi of 25mcg tab + 12.5mcg tab) and then 10mcg synthetic T3 ? Daily or split.

Im confused because in a previous post 1 grain of NDT was = to 100mcg synthetic Levo......so which is correct because thats much more?

Sorry if I am being dim here, every best wish ,G

SeasideSusie profile image
SeasideSusieRemembering in reply toGillybean1

Gillybean1

There are conversion tables that state 1 grain NDT = 100mcg Levo. They are stating the equivalent effect (bioactivity) of 1 grain NDT.

1 grain = 38mcg T4 + 9mcg T3.

T3 is said to be, in it's effect, 3-4 times more potent that T4. Therefore 9mcg T3 would be the equivalent of approx 27-36mcg T4.

So 38mcg T4 plus 9mcg T3 = 65-74mcg T4

But it doesn't have to add up to 100mcg T4 because that amount (contained in 1 grain NDT) is giving the equivalent effect of 100mcg synthetic T4.

does that mean I would need with synthetic Levo to take 38mcg (combi of 25mcg tab + 12.5mcg tab) and then 10mcg synthetic T3 ? Daily or split.

Yes, to get the equivalent (in it's effet) of 1 grain you would take that synthetic combination you mention. Whether you take it in one dose or split it is up to you. You could start off splitting so that it's the same as you're taking your NDT and see how you get on. You could experiment by taking it all at once to see if it makes a difference.

I take Levo plus T3 and I've done it both ways. I started off taking it all in one dose together and had no problem. I decided to experiment and split the dose, still kept my Levo in one dose plus half my T3 early morning, the other half of T3 late afternoon. I had no problem but after many months I realised that I had not experienced any advantage by spitting it so I've gone back to taking it all in one dose (although I do split the T3 the day before a thyroid test so that last dose is 8-12 hours before blood draw as is advised). It's just something to try and see what suits, some people find splitting is best for them, some people find taking some T3 at bedtime has it's advantages, some people are like me and take it all at once early morning. We're all so very individual and need to find what's right for us.

Does all that make sense? It's getting late and maybe don't always explain things well enough at this time of night :)

Gillybean1 profile image
Gillybean1 in reply toSeasideSusie

Bless you SeasideSusie,

For your reply and so late in the day. Im going to print off what you have said and process it on a better day.

Clearly here many of us are 'sick of being sick', I bore myself with it, going round and round in circles, BUT im not beaten yet.Now to find a Levo that agrees.

My endo always wants a registering of TSH, but how low is too low? I have never been able to get the T4 up to where I feel 'better not well' approx 18-20 ish without the TSH being non existant. He wants a recognition of TSH showing .Im currently floundering at 12-13 T4

This is another reason for following your lead with an agreeable synthetic Levo to see if I can get the T4 up, with a T3 top of range and TSH with a flicker showing......and maybe the Armour is a little too fierce and fierce on my pocket to achieve that.

I dont think after all this time that I have mastered the timings still...recently I split of a bit of my NDT a 1/4 grain at bedtime and was awake all night.... which may not happen with synthetic Levo.

As you say its very very individual......., mastering this Dio2 + Hashi's is a nightmare.

Thank you for taking the time to answer, every best wish, G

radd profile image
radd in reply toGillybean1

Gillybean1

The discrepancy comes about because medicating even a little bit of T3 up-regulates the thyroid converting enzymes so you actually accumulate more. That is why the manufacturers state that a pill (grain) said to contain 38mcg T4 + 9mcg T3 is actually bio-equivelent to 100mcg T4.

However, some think that a little far fetched and equate 1 grain to somewhere in the middle, so say about 80mcg T4. Therefore, if I was you switching from 1 grain Armour to Levo & T3 whilst also considering tablet sizes, I would do a straight switch over to 75mcg Levo + 5mcg T3, but be aware you might need to increase T3 further. And if this were so I would take the second T3 dose in the afternoon.

Gillybean1 profile image
Gillybean1 in reply toradd

Hello Radd,

Thank you for taking the time to reply and explain clearly. No wonder GP's younger than 60yrs of age (the pre Levo dispensing ones who remember NDT ) glaze over and dismiss NDT.

Do you happen to know if I switch over, do I do this the next day straight to synthetic Levo or do I have to drop down NDT for a couple of days...? I presume adding synthetic Levo will take 14 days to accumilate? So not that easy...

Every best wish ,G

radd profile image
radd in reply toGillybean1

Gillybean1,

Because NDT contains both T4 & T3 you can do a straight swop, eg one day NDT, next day synthetic T4 + T3 meds. You will need to hold dose for 6 weeks before testing and ensure to include FT3 in TFT's. Do not increase thyroxine because 75mcg is upper suggested dose until levels are tested & depending upon conversion abilities you may end up on something like 50mcg/75mcg mixed dose Levo + 10mcg T3 for example. It also depends upon the availability of your T3 supply.

You hinted at raising TSH to SsS but your aim is to replace thyroid hormone amount like-for-like so TSH would not be expected to rise. If you reduced meds slightly there is still no guarantee that TSH will shift and you are on a low dose of replacement meds anyway.

My replacement dose is relatively low compared to some so imperative to ensure best efficacy with the essential adequate iron, nutrients, and controlled thyroid antibodies to avoid long term damaging inflammation.

Good luck 😊

Gillybean1 profile image
Gillybean1 in reply toradd

Hello Radd,

Thank you for your swift reply. Understood, like for like first. Yes the reason I meant to raise up T4 to SsS was because back in 6 yrs ago I started on 1/4 grain NDT worked up to 2 1/2 grains over 2 years ,giving me an 'undetectable TSH' (Endo's unacceptable opinion) better stamina but still with Chronic Fatigue ie no stored energy, = spurts and wipeout or collapse. But my T4 then was approx 18-20, T3 in top of range, still feeling dreadful.

Back then I was consuming additional Vit/Min supplement meal drinks, and in hindsight too close to NDT meds, So much so that when I stopped them (unusual allergy to rice content) immediately, I had a massive 'thyroid-storm' 3 days later as the true effect of my meds dose became real.

Somewhere in that mess I must have missed my sweet spot, so I started working from 1/4 grain up again, to no avail.

2021 I trialled T3 only on Endos regime, I could only tolerate max 12.5 mcg T3 daily. I spent 2021 barely able to stand and only upright for 1 hr per day.

2022 back on NDT and a pinch of T3 so can stand up for 3-5hrs per day approx ,but T4 is 12-13 ,T3 5.5 and TSH 0.24..... so TSH out of range again.

GF,DF,SF, Iron/Ferritin, D, folates ok, B12 v high............. it was just a thought that although i am Dio2+ with Hashi's that 'maybe ' I need more T4 in proportion to T3, maybe my conversion is not too bad. Maybe i dont need T3...

To be honest right back at the start of this, GP refused Levo Meds as my TSH was ok, I was struggling, did antibody tests etc privately ,NHS said 'oh yes but your TSH is ok, come back when it reaches 8-10........' so started self medicating whilst waiting 6mths for Endo referral......same story for many I realise.

Thank you again very much for taking the time to respond, its a lonely business, and I am so tired of fighting for my health and to be heard as many here have clearly found...... anyway I might have been knocked down, but im not out!! so to speak.

Every best wish, G.

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