I'm looking into the terminology before my next visit to the Doctor (here in France).
When looking at the uses of Cynomel in the French govt medication data base , it states that one of its uses is for an "adjuvent treatment in thyroid hormone resistance syndrome"
I've looked up this syndrome in a French document and it has given me the translation in English too. So I am pretty sure it is accurate. It also talks of Befetoff syndrome as another term.
Is this the same thing as bad conversion from T4 to T3? Or is this something entirely different? (If this is the case I might have problems convincing doctor to prescribe it)
Why am I asking? Well my new doctor did not know Cynomel and looked it up on the data base. When I got home I wanted to see what it said and the uses. I'm wondering if the guidelines in France just limits it to very specific uses and not just bad conversion. I also noted that it is not always reimbursed. But at 5 Euros for a box this is not really too much of an issue.
Thanks for your feedback
Best regards
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lovelab
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No, it's not the same thing as poor conversion. It's something else entirely. I don't think it has specific uses. And most GPs don't know what it is, anyway. I got it just by saying I wanted it, end of. And, the GPs I've talked to about it always have to look it up. Some will give it to you because they don't know what it is, and others won't give it to you because they don't know what it is. It's pot luck, really. But, if your doctor won't give it to you, go and see another doctor. You can do that in France.
Thanks greygoose. Glad you cleared this up for me. Is there therefore an offical term for poor conversion? So I can find a paper to back it up in French.
Meanwhile, I'm hoping new Dr is going to give Cynomel to me. He seems quite an open-minded sort. I need to be a bit more assertive -it's difficult for me as I have a terrible confidence problem.
Availability: I've noticed that Cynomel is not available locally in pharmacies atm but sure it can be ordered. So looks like noone is prescribing it locally for whatever reason. However, Euthyral is available down the road.
So will pick Dr's brains on Euthyral too, supposing he knows what that is.
Also, I'm presuming that Euthyral only comes with following dose :T4 100umg + T3 20umg. Can you advise?
Does this mean it is not as easy to fine tune as one could do with combination of Levothyroxine and Cynomel?
As far as I know, there's not an official name for it. And, to be honest, I have never, ever had a conversation with a doctor about conversion. It wasn't necessary. In fact, I converted very well, I just couldn't tolerate levo. But, I didn't even tell them that, I just said I wanted T3.
In the beginning, I was given Euthyral by an endo in Paris. But for me, it was a very bad idea because it was a lot of T4, which I couldn't tolerate, compared to not enough T3 - I do have Resistance to Thyroid Hormone - although I didn't know that at the time. I needed a lot of T3. And, as you say, you cannot fine-tune the dose. It's like taking a sledge-hammer to crack a nut - all or nothing! Bang!
I very much doubt that many GPs are prescribing T3 because they don't know what it is. So, unless someone specifically asks for it, they won't prescribe it, so the pharmacy won't stock it. Not in a small town. I always had to order mine in advance. And, be warned, pharmacians don't know what it is, either. They think it's just a different brand of T4! So many times I was given T4 when it said T3 on the prescription, and I was told it was the same thing!
By the way, it's easy enough to know if you have a conversion problem. You just compare your FT4 level with the FT3. Percentage-wise, the FT3 should be just slightly lower than the FT4 level. As you're in France, you must have a print-out of your results, so post them here and we'll be able to tell you.
Oh, that's terrible conversion! The FT3 percentage should be just slightly lower than the FT4. So, you shouldn't have to have the FT4 that high to get enough T3. And, even with that, you don't have enough T3, it's far too low.
Thyroid hormone resistance is not poor conversion. DippyDame will be able to tell you her experience of it.In a nutshell it is where your body does not accept the T3 into the receptor cells. A resistance to accept T3 at a cellular level.
Just read your bio. I too had bad whiplash at 17 and wore a neck brace for 18 months in the 1980s. Not sure if they'd advise that today. Is this sort of injury relevant to thyroid in anyway?
I am still having difficulty understanding the concept of of TH resistance ... so if you have any links that could help me understand.
But I think my issue is poor conversion, maybe due to poor vitamin levels. I've been supplementing vit D 100 000 units all winter and it has only pushed me up to 74nmol (75 - 150 nmol). Folate is bottom of the range but last endo didnt want to prescribe supplements etc
Whiplash can cause damage/ stress to the pituitary gland that is mostly temporary and said to resolve after about a year. Pituitary function is important to thyroid function
I had a number of sessions of neck traction in the 1970s which recently horrified a young nurse...it helped me!!
RTH is not a common condition so several things have to be eliminated before coming to that conclusion.
A basic explanation...
In order to become active T3 must move from the serum to the nuclei of the cells ( cellular T3) if this doesn't happen because of resistance we experience symptoms of cellular hypothyroidism.
These symptoms are similar to those experienced when serum T3 is low.
Normally, T3 automatically reaches the nuclei of the cells but with RTH the cells create a resistance so that the T3 (to varying degrees) does not pass from serum to cell via T3 receptors.
If this fails to happen the T3 remains in the blood until it is metabolised and excreted having failed to fulfill it's purpose of controlling the body's metabolism.
The greater the resistance the lower the level of cellular T3
The lower the level of cellular T3 the more symptomatic and unwell the person becomes.
In very extreme cases the patient will suffer a life threatening myxoedema coma and may die.
Panic not...this is highly unlikely!!
Someone with RTH therefore needs a higher dose of T3...
This high/supraphysiological dose of T3 acts as a "battering ram" against the walls of the cells forcing some of that dose into the cells.
We need to use trial and error to work out the size of the therapeutic dose required....the smallest dose possible.
Once sufficient T3 is "pushed" into the cells and becomes active the patient will improve.
It's not a process medics embrace!!
But for some of us it is essential in order to restore health.
We have to monitor the dose by signs and symptoms, as was done nearly 100myears ago..... there are no tests for cellular T3
It can take a very long time to reach the therapeutic dose....it took me close to 3 years.
So not a quick fix!
However I would suggest you are a long way from needing to consider RTH....I explain to answer your question!
The more common problem may be low serum T3 which can be overcome with a combo T4/T3 dose.
Poor conversion contributes to low serum T3 which, if conversion is poor, must be dealt with first....optimal nutrients are essential.
SeasideSusie is very knowledgeable about the nutrients essential to good conversion.
Oh well, I get easily confused these days, so just checking. Thanks for the explanation.
Yes, thinking about it, whiplash could affect the pituitary - the brain must hit the skull a couple of times during the accident. I'd just never really thought about it before, because my problem is Hashi's.
It's my lack of memory for names that's driving me bonkers....I frequently have to use my husband as an external memory bank!!! My father was a horticulturist and could reel off the Latin names of countless plants....until he couldn't.
I remember the frustration that caused him.
Otherwise memory is fine.
Must be in the genes!!
Stay safe in this heatwave
Our 1790 stone built house has thick walls .... so thankfully is cool inside.
I have one or two techniques I use for words I forget. One is, I write them large on the calender desk pad I have, in front of my computer. So, every time I change the page, I have to write them all out again. Before, I could never remember the word 'antibiotic' for some reason. Now I can!
If it's a person's name I can't remember, I go through the alphabet: A = Alice, Ann, Alison... B = Barbara... etc. etc. etc. The name I'm looking for usually comes back to me before I get to the right letter. Works every time.
I've been supplementing vit D 100 000 units all winter and it has only pushed me up to 74nmol (75 - 150 nmol). Folate is bottom of the range but last endo didnt want to prescribe supplements etc
Was that 100,000iu per week or what?
The loading doses for Vit D deficiency (<25nmol/L in the UK) would be a total of 300,000iu over a number of weeks. If you've taken 100,000 regularly I'm surprised your level is only 74nmol/L, but I'm assuming it's improved?
Are you taking D3's important cofactors?
Magnesium is needed so that the body can convert D3 into it's usable form. You need to check which form of magnesium is right for you:
and magnesium should be taken 4 hours away from thyroid meds, usually best in the evening as it's calming and you don't want to be falling asleep at work or on the way home!
Also needed is Vit K2-MK7. D3 aids absorption of calcium from food and Vit K2-MK7 directs the calcium to bones and teeth where it is needed and away from arteries and soft tissues where it can be deposited and cause problems such as hardening of the arteries, kidney stones, etc.
90-100mcg K2-MK7 is enough for up to 10,000iu D3.
D3 and K2 are fat soluble so should be taken with the fattiest meal of the day, D3 four hours away from thyroid meds if taking D3 as tablets/capsules/softgels, no necessity if using an oral spray.
For D3 I like Doctor's Best D3 softgels, they are an oil based very small softgel which contains just two ingredients - D3 and extra virgin olive oil, a good quality, nice clean supplement which is budget friendly. Some people like BetterYou oral spray but this contains a lot of excipients and works out more expensive.
For Vit K2-MK7 my suggestions are Vitabay, Vegavero or Vitamaze brands which all contain the correct form of K2-MK7 - the "All Trans" form rather than the "Cis" form. The All Trans form is the bioactive form, a bit like methylfolate is the bioactive form of folic acid.
Vitabay and Vegavero are either tablets or capsules.
Vitabay does do an oil based liquid.
Vitamaze is an oil based liquid.
With the oil based liquids the are xx amount of K2-MK7 per drop so you just take the appropriate amount of drops.
They are all imported German brands, you can find them on Amazon although they do go out of stock from time to time. I get what I can when I need to restock. If the tablet or capsule form is only in 200mcg dose at the time I take those on alternate days.
The Vit D Council, Vit D Society and Grassroots Health all recommend a level of 100-150nmol/L with a recent blog post on Grassroots Health recommendeding at least 125nmol/L.
For the other important nutrients, recommended levels are:
B12 - top of range
Folate - at least half way through range
Ferritin - half way through range although some experts say that the optimal level for thyroid function is 90-110ug/L.
Optimal nutrient levels are needed for thyroid hormone to work properly and aid good conversion of T4 to T3.
The vitamin D I have been taking one dose of 100K once a month (an oil you mix in a glass of water before lunch ). It has gone up from 50 to 74 nmol since winter 20/21 but have only been on 100K this winter (was previously on 50K).
I have just noticed that my new prescription is for 50K (arghhh) , so Ill see if I can get this increased. I think I have low stomach acid, because of acid reflux for years, which only disappeared once on Levothyroxine.
I will have to go to the pharmacist with the references you mention.
Ive never taken Vit K so I ll ask the pharmacist and
as for magnesium, I was taking it for a few weeks and then I had a strange episode of very high blood pressure and had to go to ER, so I stopped all self medication in case it was the problem. But now all seems to be fine and Ill maybe talk to pharmacist again.
I believe my problem was Clipper tea which has licorice root in it and I'd had rather alot of it. Needless to say I dont drink it now.
Impaired Sensitivity to Thyroid Hormone: Defects of Transport, Metabolism and Action
Alexandra M Dumitrescu and Samuel Refetoff, M.D.
Author Information
Last Update: August 20, 2015.
ABSTRACT
Defects along the pathways leading to TH action can manifest as impaired sensitivity to TH. Six steps are presumed to be required for the circulating thyroid hormone (TH) to exert its action on target tissues. For three of these steps four distinct phenotypes have been identified in humans. The clinical, laboratory, genetic and molecular characteristics of these defects are the subject of this chapter.
The first defect, recognized almost 50 years ago, produces reduced sensitivity to TH and was given the acronym RTH, for resistance to thyroid hormone. Its major cause, found in more than 3,000 individuals, is mutations in the TH receptor ß (THRB) gene. More recently mutations in the THRA gene were found to produce a different phenotype owing to the distinct tissue distribution of this TH receptor. Two other gene mutations, affecting TH action, but acting at different sites were identified in the last 10 years. One of them, caused by mutations in the TH cell-membrane transporter MCT8, produces severe psychomotor defects. It has been identified in more than 320 males. A defect of the intracellular metabolism of TH, identified in 11 members from 9 families, is caused by mutations in the SECISBP2 gene required for the synthesis of selenoproteins, including TH deiodinases.
Knowledge of the molecular mechanisms involved in mediation of TH action allows the recognition of the phenotypes caused by genetic defects in the involved pathways. While these defects have opened the avenue for novel insights into thyroid physiology, they continue to pose therapeutic challenges. For complete coverage of this and related areas in Endocrinology, visit the free online web-textbook, endotext.org.
Resistance to thyroid hormone (RTH), a syndrome of reduced responsiveness of target tissues to thyroid hormone (TH) was identified in 1967 (1). An early report proposed various mechanisms including defects in TH transport, metabolism and action (2). However, with the identification of TH receptor beta (THRB) gene mutations 22 years later (3,4), the term RTH become synonymous with defects of this gene (5). Subsequent discoveries of genetic defects that reduce the effectiveness of TH through altered cell membrane transport (6,7) and metabolism (8) have broadened the definition of TH hyposensitivity to encompass all defects that could interfere with the biological activity of a chemically intact hormone secreted in normal or even excess amounts. In this revised chapter, we cover all syndromes resulting from impaired sensitivity to TH, using the recently proposed nomenclature (9) (see Table 1).
Thank you. Will have to read this when Im a bit fresher . My eyesight is just about giving up tonight... had a look at the links quickly... endotext.org and saw one of the editors of the site is a Dr in Lausanne which is interesting, as local to me.
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Cynomel Aventis-Sanofi
How much T3: T4 in blood ?
T3 75mcg capsules in Mexico 
I've just seen my first Endo. 
T3 Cynomel France.
