What does the body do with Levothyroxine? Levothyroxine is (F)T4 isn’t it?
A few days ago I read something that’s confused me:
“It is the T3 that is biologically active and regulates your body’s metabolism.”
So why isn’t T3 standard treatment/medication like Levothyroxine is?
We wouldn’t have weight gain if it was and we’d lose it.
I have a horrible feeling though that I’ll be told it’s not as simple as that and it doesn’t work like that !
Edit:
Also this bit:
“FT3”
“This is usually only used in testing for hyperthyroidism or assessing its severity.”
Why’s it not part of the testing all of the time? It would help to know what the levels are wouldn’t it? FT3 is a part in the whole functioning of the thyroid! Makes no sense!
So we’re just having part of the problem treated!? We’re never going to be well when everything isn’t replaced and treated!
Making out that Levothyroxine solves it!
So infuriating!
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WallFlower0610
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The body secretes mostly T4 and a little T3. T4 is converted into T3 in various organs (gets complicated). Liothyronine has a half-life of 24 hours so even if taken two or three times a day there will be fluctuating levels of fT3. This isn't as important as it sounds since tissues take several hours to respond to T3. Levothyroxine has a half-life of seven days, so taken once daily gives stable T4 and T3 levels.
Some tissues need T4 so they can convert it to T3 as and when they need. Levothyroxine is much cheaper that liothyronine, especially in the UK where we pay an incredible price. This is why levothyroxine is prescribed. Some patients need some liothyronine to make up for the T3 that the thyroid produces. Some patients need abnormal amounts of T3, I put this down to complex issues like endocrine disruption and poor conversion.
Levothyroxine is fine for many patients but not for all. Doctors generally do not accept some patients need liothronine (L-T3), often in higher doses than the thyroid secretes.
“The body secretes mostly T4 and a little T3. T4 is converted into T3 in various organs (gets complicated).” - Doesn’t if the thyroid has been killed off or removed. Me being one of them who had mine killed off. Really wish I didn’t.
What converts T4 to T3?
What does ‘half-life’ mean?
What abnormal amounts of T3 are they?
Why don’t they ‘accept’ patients need T3? If the thyroid has been killed off or removed then there’s nothing to release it and none to be released...? Do they not accept those patients need T3 supplemented? Surely not. Why don’t they accept those patients need T3 supplemented?
In healthy people the thyroid secretes mostly T4 and the body converts T4 to T3 using enzymes called 'deiodinase' in various tissues. Some of this deiodinase activity takes place in the thyroid, so the thyroid does two things, it secretes T3 and T4 and it converts some T4 to T3.
Endocrinologists tend to believe that patients will be OK on levothyroxine only because they will convert the T4 to T3 as they need it. This works for many patient, it doesn't work for quite a few patients - endocrinologists are reluctant to accept this.
Levothyroxine has a seven day elimination half-life. That means if you take 100 mcg levo today then in seven days you will still have 50 mcg left. If you take 100 mcg today there will still be 90.5 mcg in your body tomorrow So, you have less than 10% variation in your T4 levels from day to day. Very stable dosing. Furthermore your body will convert T4 to T3 as it needs it so T3 levels will tend to be very stable also. This is great for patients who do well on levothyroxine. Unfortunately, some patients do not and need T3.
Liothyronine (L-T3) has a 24 hour half-life. If you take a 20 mcg tablet today there will only be 10 mcg left the same time tomorrow. Endocrinologists are concerned about these fluctuating levels of hormone, even with twice daily divided doses levels still fluctuate a lot. i think this concern is unnecessary because (for complex reasons) T3 doesn't act instantaenously, it takes several hours to have effect and this smooths out any fluctuations. Many endocrinologists will tell you they are worried about the varying T3 levels when their real concern is the price of liothyronine in the UK.
A few patients need abnormal amouts of T3. By abnormal I mean amounts that give abnormal fT3 results, more than a healthy person would have. Taking about 10-20 mcg liothyronine daily would replace the T3 your thyroid secretes and converts from T4, you would get the same amount as a healthy person gets from their thyroid. Some patients need over 100 mcg liothyronine, these are not normal amounts.
I share your frustrations that endocrinologists are not prepared to prescribe T3 medication, it's a battle we have been fighting for a long time.
I don't think it's for medical reasons. I think it's all about cost. I understand that in mainland Europe levo and lio cost roughly the same. In the UK .... they emphatically do not!
I can't help feeling that if lio cost the same in the UK as it does say in Germany or France, levo wouldn't be the third most prescribed medication, but instead there would be LOADS more free T3 testing, LOADS more lio prescribed and LOADS of happier hypos.
Not sure you're right, there. It's getting harder and harder to get doctors in France to test FT3 because they don't know what it is, what it does or how it works. Some doctors will prescribe T3 but not all: I had one doctor prescribe me T3 because he didn't know what it was, and another refuse to prescribe it because he didn't know what it was. And, they will openly tell you, for the most part, that they don't test FT3 because they don't understand the results.
Once upon a time we were prescribed NDT (natural dessicated thyroid hormones) from 1892 onwards - no blood teststhen but doctors knew all the clinical symptoms of hypothyroidism and prescribed 'natural dessicated thyroid hormones'. It also contains all of the hormones a healthy gland would do.
Then levothyroxine plus blood tests were introduced by Big Pharma which slowly became the biggest replacement worldwide. It made Big Pharma profitable along with blood tests.
NDT was withdrawn through misinformation by the Association and without notice and one of Thyroiduk's Advisers wrote a Rebuttal to them and despite him writing to them each year for three years for a response - they never did. Even if they knew how important NDT was to patients they did not care one iota that for some very unwell patients their need was for either T4/T3, T3 only or NDT. Those for whom levothyroxine restored their health would not be on this forum.
p.s.NDT also contains all of the hormones a healthy gland would do.
Also ask GP to test B12, Vit D, iron, ferritin and folate. Everything has to be optimal,
Always get a print-out of your results, with the ranges, as labs differ in their machines and so do the ranges.
There's no rush for a response. Just take your time as in reality we shouldn't be searching the internet but for us who're hypo it is been a godsend as we can exchange views or have more knowledgeable people to try to help us along to good health. It is trial and error but when we get to a 'sweet spot' and feel well again its been worth it, despite the ridiculous guidelines.
I agree! money does seem to be a huge factor, why patients are often talked out of trying T3, and why, it's not easily prescribed....it's a fight to get it.
I used to get it in North America, but it's not available here in Spain, and so I have to buy it online, at massively increased prices.
Your post makes me smile, as you have ' summed up ' the stupidity of the system we try and get well within.
I guess that is why there are over 100,000 members on just this one thyroid help forum.
I'm just so grateful I found this amazing site and with a little help and a couple of books have turned things around for myself.
I'm with Graves Disease post RAI thyroid ablation, a treatment I deeply regret, and am now managing lingering Graves, thyroid eye disease ( caused by the RAI ) and hypothyroidism and I now self medicate and stay away from the medical professionals.
Well, where do I start - ok - Graves is an autoimmune disease, it's in your blood and DNA.
There is usually a genetic predisposition and something happened to trigger your susceptibility to this poorly understood and badly treated autoimmune disease.
The thyroid is a major gland, the body's engine, and responsible for your mental, emotional, physical, psychological wellbeing, your inner central heating system and your metabolism.
When your immune system attacks your thyroid the symptoms can be extreme, some life threatening, and some simply just a little odd. Initially your body goes into a ' hyper ' phase and the medical profession calm you down, back into range, with drugs that block your own thyroid hormone production.
Apart from confirming your disease by checking your antibodies, unique to Graves Disease, they have no idea how reduce, control, this aspect of the disease, and so sadly they seem to think the best option, is to destroy the thyroid so the symptoms go away which leaves you hypothyroid, as the medical profession believe they know how to control this debilitating health condition.
Your thyroid is the victim in all this not the cause - the cause is your immune system going haywire.
I have Graves Disease, diagnosed 2003 and treated with RAI in 2005 and was on 100/125 Levothyroxine for about 10 years, and offered anti depressants rather than a full blood test. I became very unwell in 2014 - details on my profile page -sorry, I don't want to revisit all that on here now - and spent around 18 months on an NHS not so merry, merry go round : the only answer I got was a low ferritin - and I knew it was so much more than that :
housebound I thought,
" Well, I had Graves, maybe it's come back " - I bought a book - Graves Disease - A Practical Guide - written by Elaine Moore - then I bought a laptop - and found this amazing forum - kept reading and now it's 2020 :
I returned to my doctor requesting a T3 and T4 blood test, and testing for vitamins and minerals and was refused - I stayed sitting down presenting my findings and 7 pages of hand written facts to substantiate my request - I managed a blood test for T3 and T4 providing I paid for it :
£34 gave me a T3 of 4 and a T4 of 20 and an increase in T4 back to 125 mcg daily and a reluctant referral to endocrinology. When I got to endocrinology my TSH was suppressed at 0.01 and so this was given as the excuse as to why I couldn't have a trial of T3.
I then went on to do it for myself, and purchased some T3 and it was a light bulb moment.
I thought I owed it to myself to also try Natural Desiccated Thyroid and found it ' softer ' on my body and so this is where I am.
I say lingering Graves as it's an auto immune disease so I think when I look back ( I'm 73 ) I see my years of poor health and no answers from various doctors, as part of the whole.
I am dyslexic and this is detailed in Elaine Moore's research, as well as my left handedness:
I have always been of a nervous disposition, and Graves tends to be a stress and anxiety driven auto immune disease.
My trigger was being physically threatened and verbally abused by a work colleague some 4 months prior to initial symptoms and then my trying to get the said individual reprimanded in a company who gave me no real support or understanding, and ultimately decided to close down the unit where I was manager, rather than support the sixty odd volunteers who tirelessly supported the charity.
Obviously I've written all this with hindsight, as at the time, I had no idea of the bigger picture, just thought I had Graves Disease since the Carbimazole worked, I could work, and I felt ok, and the doctors told me I'd be even better after the RAI and why would I not trust the doctor, they knew more than me, who was " I " to question, what did I know ????
Well since Graves is an auto immune disease, removing the thyroid doesn't negate your blood test, so yes, you still have the auto immune disease.
However, Graves Disease generally only gets diagnosed when it attacks the thyroid - because the thyroid is a major gland and when the thyroid is under attack by your own immune system the symptoms experienced can be many, with some of them life threatening and needing medical help, as you can't manage these symptoms with a paracetamol and a good night's sleep.
Graves seems to be a stress and anxiety driven auto immune disease so might suggest you look back at months before your diagnosis to try and identify what ' set off ' your immune system to attack your body, and more especially your thyroid.
My trigger for a diagnosis of ' something ' happened about 4 months after being physically threatened and verbally abused by a work member of my team. Looking back now I believe I was undiagnosed hypothyroid for many years but there you go :
I still live with some back pain, though it's not acute as it was, and looking back I worked through my pain and worked myself into the ground, rather than ' give in ' .
You can consider T3 with T4- Levothyroxine, tablets containing both T3 and T4 or NDT and if you feel ' iffy ' maybe look at the other options first.
Start a new post with your latest full thyroid blood test results to include the antibodies and vitamins and minerals as already detailed and you will receive help on how to get better, first through the NHS, as that has to be the first step forward for all of us to take.
“Well since Graves is an auto immune disease, removing the thyroid doesn't negate your blood test, so yes, you still have the auto immune disease.”
Sorry I’m being dense, I don’t understand. Does that apply to if you’ve had RAI as well?
I was 13/14 when I was diagnosed and probably symptomatic long before then. I didn’t have anything stressful happen to me or in my life - you don’t that age. I was really poorly in the lead up to being diagnosed - not that anyone had put two and two together, I only ended up being tested for things because I was in hospital for an appointment about something else - and for over 10 years afterwards. Consequently I don’t remember a lot from back then. I’m now 29, 30 this year.
Well yes, the radioactive iodine is taken up by your thyroid and slowly disables this major gland by slow burning it out thereby rendering it dead, disabled and destroyed.
There is a genetic component to Graves Disease and you probably need to be looking at your your wider family, for any thyroid health issues, maybe a generation away from you.
You can read all this, and much more, on the Elaine Moore Graves Disease Foundation website, should you wish.
I would imagine as your thyroid burnt out so would any of it's contents and presume if any anti bodies were in your thyroid they would have been destroyed as well.
My last comments may have been a little misleading as Graves is said to be stress and anxiety driven.
Stress and anxiety come in many different forms and as you have said you were ill from a very early age, and at an age where you may not have known how to process what was happening to you.
Graves has also been associated with a sudden shock to the system, like a car accident, or the unexpected of death of a loved one.
There is a greater incidence of Graves Disease in war-torn areas of the World.
Long term pain causes stress, as does long term illness, as does living in difficult circumstances, and it's also down to genetics as to how we deal with ' stuff ' that happens in our day to day lives.
I don't know where you live but in the UK you ask your doctor to help you and this may mean a referral to an endocrinologist.
You also need a full blood panel to include your TSH,T3,T4 and the vitamins and minerals as detailed on this website.
You might feel better with an increase in your existing thyroid hormone, and this is the first option as to optimum wellness.
If this doesn't achieve its end you may be granted a trial of T3 along with your T4 and if possible it's better stay within the system with someone to support your progress.
You need to read up yourself on all things thyroid so you are better equipped to know how your body works and what you can do to improve your situation.
If you find you are getting now where within the medical profession you might consider self medication. It's not easy, there will be bumps along the road and you must feel confident in your knowledge so initially I'd suggest reading up about Graves and Hypothyroidism.
The Elaine Moore Graves Disease Foundation website helped me as did the book Your Thyroid and How To Keep It Healthy written by a doctor who has hypothyroidism - Barry Durrant - Peatfield.
I source my thyroid hormone replacement from the Far East and currently there a big problems within the supply chain and product availability difficult and then despatch is delayed because of the current pandemic. It's currently not an easy option.
I take NDT which is pigs thyroid dried and ground down into tablets called grains, and believe it is known as Natural Desiccated Thyroid throughout the world.
I have sourced T3 from Greece when I trialled this alongside my T4 but couldn't maintain the supply chain.
I have no knowledge of the T3 and T4 combined tablet and depending where you are in the world its brand name may change.
If you read a few posts on this forum you will see many people being advised to arrange a full blood test, ideally through their own doctor, but if there is no support there you can arrange this yourself and links are given to private companies who process blood tests.
These private companies along with much more information are available on the Thyroid uk website, which is dedicated to and supports all people in seeking better thyroid health treatment. The redesigned website is worth dipping into and you can join, become a member and help support this very worthwhile charity.
I researched my intended suppliers and received a couple of private messages from people from various websites.
I have never taken a T3/T4 combo tablet and am sorry if I misled you.
Tempting to just go straight to the private companies as highly unlikely the GP and NHS will give me the tests I want and T3 - going from what I’ve read on here, Thyroid UK and other sources.
Initially I went to my doctor and asked if she would support me with a prescription of Natural Desiccated Thyroid - she refused.
About wo years later after learning from this forum I asked for a full blood test to include the vitamins and minerals as suggested on the Thyroid uk website and this forum. My doctor refused but said I could have a T3 and T4 blood test if I paid for them - and this I did - for which the NHS charged me 34 pounds.
I asked and was referred to endocrinology where I was refused a trial of T3 because of my low/suppressed TSH and told I was overmedicated though my T3 was just 50% through the range.
I then decided to do it for myself and purchased T3 and NDT from abroad, without a prescription. Both T3 and NDT worked for me, and gave me back my brain and relative wellness.
I prefer taking the NDT as I do not have a working thyroid as mine has been burnt out in situ by RAI - the treatment the NHS gave me for Graves Disease in 2005. I am replacing like with like, as NDT contains all the same known thyroid hormones as my thyroid once supported me with namely T1.T2.T3.T4 and calcitonin.
Some people take Levothyroxine -T4 only and some people take Liothyronine - T3 only :
There is no equivalent T4 is T4 and T3 is T3 :
Some people take T3 and T4 doses together and since T3 is said to be about 4 times more powerful than T4 you need to know your T3 and T4 blood test results before you start as you may need to reduce down your T4 dose to accommodate the T3 dose :
Other people take a compounded tablet of T3 and T4 made to their specific requirements, and other people take branded tablets of a T3/T4 combo :
Some people take Natural Desiccated Thyroid which contains T1.T2.T3.T4 and calcitonin :
All any one is trying to do is find a thyroid hormone replacement that gives them a better QOL and improved health.
I don't know what to say to you as I don't understand your question, and before switching or changing any dose of any thyroid hormone you'll need to have a full thyroid panel so that the results and ranges can be seen in total and so you have a bench mark to work from.
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