I know that some people take T4 only and do well but so many have to fight for the T3 they need and one of today’s posts got me thinking because SlowDragon enlightened us on how to calculate levo dosage based on weight
I haven’t taken it yet but my endo prescribed a starter dose of 50mcg/day and I’ve calculated that eventually I ought be taking 120mcg of levo because I weigh 74.8kg
At the moment I take glandulars and was doing well and I believe this is because they contain both T4 and T3 but I’m now considering either NDT or the conventional route because since the formula of the glandular has changed, I’m not getting on well with them
My question is: if an endo agrees to “eventually” prescribe T3 - should I need it - would I likely in theory have to take a lot less levo than 120mcg and if so, what’s the average ratio of T4 to T3? All theoretically speaking of course
Thanks
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A spreadsheet with several active formulas which work out possible levothyroxine requirements including NICE NG145 guidelines. These formulas are referred to in the document above.
This is an Excel spreadsheet but is likely to work in other spreadsheet software.
You need what you need. Arithmetic might help in guiding a direction but the reality is that we are all individuals with different needs. You might find the tiniest amount of T3 makes all the difference, through the 10:1 ratio (claimed to be what healthy people produce), 4.2:1 (around the same as desiccated thyroid products) through to 100% T3.
Calculating doses by weight is just a rough guide. It is not intended to be an ultimate forever dose. You need what you need, but the weight calculation gives you a ball-park estimation to aim for, and you adjust from there according to your needs. I cannot stress that enough.
Whether or not you need to reduce your levo when adding T3 depends on your FT4 level. Your FT4 level depends on how well you absorb, how well you convert, etc. It has to be decided on a case to case basis. There is no one-size-fits all. So, trying to guess in advace about what might happen in the future if... is rather a pointless exercise.
Ratios are for euthyroid people. Hypos rarely react like euthyroid people. How much levo you are likely to need when taking T3 is an extremely personal thing. Myself, I need zero T4 - I'm better off without it. Others need their FT4 to be quite high in range, even when taking T3. It has nothing to do with ratios but everything to do with your individual needs. One step at a time, that's my motto. You'll know when you get there.
Should have added that with any hormone, you start low and increase slowly, until you find your sweet-spot. With levo that means a starter dose of - usually - 50 mcg - and increasing by 25 mcg every six to eight weeks. With T3 it's 5/6.25 - depending on pill size - to begin with, and increases of 1/4 tablet every two weeks or longer, depending on how you feel. That is how you find your hormonal requirement. You cannot calculate it in advance.
It's the Frees that are the most important - FT4 and FT3.
The difference is that the T3 test - or TT3 to give it its full name - is the total amount of T3 in the blood, both bound and Free. But, only Free is available for use by the body. Same for T4/FT4.
I always have to emphasise when talking to gp, that I need T3 testing because it’s a component of my glandular, so should I really be asking for the frees instead? I hope not because after all this time and just getting someone on my side I dread having to fight to ask for a change of test
Greygoose's post is a good reply to you. I and the team have been studying the working of the hypothalamus-pituitary-thyroid axis for over ten years (mainly as regards the changes between being healthy or having no thyroid wrt to TSH's relationship to FT4 and FT3 in the state of T4 therapy). We now have to come to the conclusion that there are almost infintely different ways in which individuals express the axis in health, and similarly infinite ways in which one responds to therapy. With this problem, some loose guides can be made (but they are not set in stone), with about 1.6-2.0 mcg T4/kg body weight However this is a crude starter as a "target". Such is the complexity of the whole axis that it boils down to setting patient response over biochemical parameters. Add in T3 as an additional thing to be considered, the patient response is often contradicted by the diagnosis using biochemical parameters alone. This again makes response superior to fine tuning - and any perceived extra risks such as osteoporosis and atrial fibrillation are tiny compared with the benefits.
With gluten and dairy intolerances, what sort of improvement might one expect by going strictly gf for instance in terms of efficacy of meds/glandulars/supplements? I definitely feel better when not having it and by that I mean I don’t get bloating/stomach cramps/intermittent diarrhoea/constipation/fluid retention but physiologically, what is actually happening to enable those improvements?
And this you won’t be able to answer but why is a really good French loaf so attractive to the palate? So damned good warmed, with a knob of salted butter. Unfortunately for me we have a master baker in the town and his bread is irresistible. From time time
I manage months and months gf but I always relapse
Hilarious tattyboogle. Might just be worth a try. Thing is, as with many addicts, when what they crave becomes unavailable to them they settle for some other inferior and sometimes lethal alternative
I jest of course. I can do it but sometimes I choose to let my desire overcome me. I fall off the waggon for a week or so then drag myself back onto it and begin the long haul back to ridding my body of the effects. It’s a horribly self-abusing destructive behaviour which I readily recognise and I should rephrase the above sentence. I don’t fall off the waggon, I wilfully climb down with all my wits about me and walk into the bakers. Insane behaviour
I discovered that introducing T3 successfully takes time, patience, determination and careful monitoring.
Numbers are not the best guide, signs and symptoms are!
Without excellent advice like that here, from greygoose, I may never have recovered!
I do not tolerate T4 but had had it prescribed for over 20 years only to find my health deteriorating to the point that I could barely function. My then GP had no solution and I knew little about thyroid disease
I found this forum and the real experts, and began to learn from them and from much reading.
After much trial and error titrating T4/T3 ( and time) I eventually discovered that I need high dose T3-only....and crucially, why!
I understood that I was dealing with a powerful hormone so did my " homework".
I decided to self medicate.
It went against all I'd been advised by medics, the endo I visited was adamant that I did not need T3. We parted company!
Instead, I trusted the enlightened advice of experienced and knowledgeable forum members, followed it and listened to my body.
The scaremongering by medics about heart attack, stroke, osteoporosis etc did not deter me. Research suggested otherwise.
A recent heart scan ( my GP was concerned) showed a healthy heart. A grazed knee is the worst I've suffered from the odd trip up....and I'm now aged 76!
I no longer relied on lab results much to my current GP's horror who asked how I monitored my dose. My reply. "The old way....signs and symptoms!". Oh!
After much explanation from me she now accepts what I do and has seen my improvement....but I still don't think she is particularly happy!
It was not a quick fix, I persisted for a very long time.
I had decades of damage to "repair".
One day I realised that I felt much better...I had eventually reached my therapeutic dose!!
I didn't expect to recover "youth" but I'm very happy with the improvement the correct dose of T3 has given me.
I now function relatively well...and without brain fog!
So yes, with T3 it's all about individual needs....not about numbers.
You won't know what you need until your body tells you!
Thank you DippyDame, that’s a really good story and inspiring too
Probably not many people are on T3 alone so I imagine then that large numbers of us ought to be. It would be interesting to know the stats
Out of interest how much T3 did you end up on?
Can I ask the name of the supplement no longer working? Metavive is the only one I know of that has been reformulated and many think it does not work the same since.
You’re so lucky fibrolinda, I found it to be an excellent product before and as far as I can find out, there’s nothing else like it. Many of the others on the market have all sorts of rubbish added or are merely extracts rather than the whole gland
Wonder why for some it just doesn't work anymore. It was a hectic, stressful time when I changed to the new formulation and I didn't pay any attention or thought to it till read how for some it was disastrous. No idea what I would have done😯. I am so sorry you are in this situation...
A question to answer tomorrow as it’s late now but can I ask what brought you to metavive and do you take the porcine or bovine one? Also, what about adrenavive, do you take that too?
Sorry just saw this... I was taking thyroid s but it became too expensive and stressful to buy so after seeing it mentioned on here I ordered some metavive, worked up to dose I am on now (2x metavive 11, porcine) with blood tests and actually feel better than I did on Thyroid s... Calmer if that makes sense? I have never taken adrenavive.
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