Hi Folks.Would people say that ERFA has higher percentages of T4 and T3 than in Thyroid S generally? I am presuming it's purer as there are less binders, fillers and chemicals in the ERFA.
If anyone has switched from Thyroid S to ERFA, any advice on dosing levels (eg. had to increase or decrease, symptoms etc), would be much appreciated
Thank you!!
I don't think we have any reason to care exactly what percentage of T4 and T3 they have. (Assuming you mean as a percentage of the whole tablet.)
Both contain 35 micrograms of T4 and 8 micrograms of T3 according to the companies.
The list of excipients in Thyroid S might be longer but I don't have any evidence that there is a greater quantity in total! We simply do not know.
Thyroid S tablets weigh around 114 milligrams. But I don't have any Erfa tablets to weigh!
60 milligrams of desiccated thyroid in a tablet weighing 114 milligrams is just over 52%.
But 35 micrograms of T4 is around 0.0307% of a tablet. And 8 micrograms of T3 is around 0.007% of a tablet.
However, that is just the technical measurements. And what really is important is how the person taking them feels. I have no answer to that, I'm afraid.
And if anyone does know the weights of any Erfa tablets, please let me know! Maybe you have some tablets and a milligram scale. 
(Typos and arithmetic corrected!)
Wow, thank you 😄, that's very technical information, it's helpful to know this, so much appreciated. I am wondering what people's experiences are when they switched over, some helpful hints maybe.
Thanks for the information and advice 🙂
By the way, no milligram scale here 😄, but I do have ERFA which is slightly smaller and flatter than the Thyroid S. It also feels lighter and a lot easier to chew and dissolve.
I switched the other way, from ERFA to Thyroid-S when ERFA changed country of manufacture and I no longer got on with them. I'd say Thyroid-S are probably slightly weaker, and I think I added in 1/4 grain at the time. However I later increased by another 1/4 grain and felt better than I had at all previously, so I hadn't been at my optimal dose anyway. You could probably try on a slightly lower dose of ERFA and see how you get on.
What are you on now Framboise? Are you still on the Thyroid S?
Yes, I'm still on Thyroid-S, now taking 3.25 grains. I haven't had any problems with it so far, but I didn't buy any of the 2022 batches and went straight from a 2021 batch to a 2023 one.
I started with Armour in about 2004, switched to ERFA in 2009 when Armour reformulated, and then switched from ERFA to Thyroid-S in 2012 when ERFA moved from Belgium to Spain for manufacture. Something was different in the tablets and I no longer got on with them. Of all those though, I had liked ERFA best, when it was working well for me.
I think with NDT brands you just have to try it. I've been on several different brands over the years but not Thyroid S. It all about how your body responds to each one. Beyond any variance of the active ingredients content there isn't really any other way but to try it. Some people are sensitive to specific fillers.For me it's been more about whether that brand is reliable in its consistancy of content more than any other factor. For me it's also been about other Co factors such as B12 and going GF that's given me the best results from my NDT.
However a pharmacist once told me it's not just the active contents and fillers but how the tablet is compressed and their release mechanisms that can make a difference in how you respond.
Hope all goes well with your transition across. Fingers crossed.
Thank you. I am gluten free but I don't take B12 as I was OK according to a blood test a while back. I did take a high strength B12 supplement a month ago but had a reaction so I stopped. It's just a case of trial and error, as with all thyroid meds, I am coming to realise. Thanks for your thoughts.
This might also be of some interest:
Thyroid S Batches
A summary of known and suspected potency of Thyroid S batches.
helvella.blogspot.com/p/thy...
Last updated 2024/01/03
Would be good to have such detailed information about Erfa and every other product! But I'd prefer it if the companies actually published this on their own websites.
Absolutely, I totally agree. These manufacturers should be publishing all ingredients, potencies etc on their bottles, leaflets and websites like all medical pharmaceutical products are supposed to. No wonder medics are skeptical about NDT.
Well, the USA and Canadian companies do list all ingredients!
But, in general, there is nothing public about potency testing of anything else. Might exist behind the wall of secrecy - i.e. FDA and MHRA might get reports about each batch of everything.
I confused by this Helvella as a UK pharmacist told me the NDTs listed on the NHS pharmaceutical list have to perform within the same tolerance as other pharmaceutical medications. Several NDTs have been dropped because they failed to do so. Erfa and Armour Thyroid remain on the list.
"same tolerance as other pharmaceutical medications" is a bit odd as the tolerances vary by product.
Many are 90 to 110% but levothyroxine is 90 to 105%. And I think some others have tighter tolerances.
Further, those tolerances need to be adhered to up to expiry date.
But we as members of the public have no idea if one batch of some levothyroxine starts out at 101% or 99%. We only know the acceptable tolerance range.
I'm not convinced about the dropping product approach. After all, the manufacturers are not allowed to continue supplying if there is a known out of range issue. We saw that with Nature-Throid and WP Thyroid and NP Thyroid.
If every product that is ever found out of compliance is immediately dropped, we end up with none. After all, Armour Thyroid has had its issues. The usual approach is to institute some sort of recall and do further testing before more product is allowed.
The potencies of Thyroid S appear well within the 90 to 110% range!
Hi Helvella - Think you may have misunderstood me a bit or maybe I wasn't clear enough...?? Sorry if the latter. Tolerances will be within that band of that particular group of medications. I didn't mean to imply that all medications have the same tolerance applied. I don't have enough knowledge of pharmaceuticals regulations to apply that as a rule.
Thyroid S has never been listed on NHS prescription list. Acella NP was but was dropped because it continued to perform higher than the upper tolerance allowed. Simular with WP and Nature thyroid who consistantly didn't perform within the tolerances allowed. They too were on NHS list but were dropped because of this. That was what I was told by my pharmacist.
Can't comment on why other ndts are not listed on the NHS prescribing list am afraid. NHS commonly limits what they will allow to be prescribed, increasingly so, according to my GP. Eg my GP can't prescribe the necessary needles and syringes I need because only all in one ones are now listed. Yet they can prescribe me glass B12 vials!! So they have to obtain the needles and syringes direct from the hospital instead. Bonkers I know but true. Lol...
Yes - but as we have no approved desiccated thyroid product, there is no precedent for a tolerance range for desiccated thyroid!
I am unconvinced that the NHS/MHRA actually tests desiccated thyroid for potency on an ongoing basis. And we now have an agreement that the MHRA can rely on testing by the FDA (and some other non-UK bodies).
It would seem far more credible for them to accept FDA assessment than to issue a ban which probably can never be revoked.
Im sorry but that just is not entirely true or one would follow the other and no NDT would be listed. NDT has been listed for years.... And as you know prescribed many years before levothyroxine or Liothyronine was invented. It has never had to be approved... (Though that looks likely to be changing in the future) No approved NDT in this country is beside the point. And actually that's the case because it was not and it would seem still isn't required to be approved. However who decides what is listed on the the NHS Formulary is another matter. There are other medications that are 'approved' but have been dropped of the nhs formulary list. Ask your GP. So these are two separate things not necessarily interelated.
I meant to add as for the testing of individual medications.... I'm afraid I don't know the protocol but I guess that it would not be uncommon for countries/bodies to share data.... Whether they do or don't, I don't know. I just know what my pharmacist told me who was told what I have passed on.
I think it is all about money to be honest. NDT's are probably more expensive to produce than Levothyroxine and due to being totally synthetic, easier to regulate than a more natural product. On discussion with my supportive GP, he has told me that the NHS have, and are cutting out many medications, assessments and treatments for numerous conditions purely due to lack of funds in the pot. That says it all to me, and I'm not surprised after having the NHS as an employer for over 18 years.
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