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Thyroid UK
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Is Levothyroxine Always Perfect?

Allopathic doctors almost always condemn NDT as an inferior alternative even though it has successfully been used for almost 120+ years. Levothyroxine sodium is not without it's own problems. This is a journal article from 2005 which discusses the problematic history of the synthetics. Next time your GP trashes NDT you might want to give them a copy of this. PR

PS Thanks to Lorraine at: facebook.com/thyroidpetitio...

"Current issues surrounding levothyroxine include: controversy about research, the number and types of recalls, the lack of a single reference-listed drug for comparison, and conflicting claims about the bioequivalence of various formulations."

"In a subsequent letter, dated June 24, 2004, and posted on the ATA website, the ATA, TES, and AACE reacted to the FDA decision to approve substitutes for levothyroxine stating that they were "deeply disappointed that the FDA has moved to approve generic levothyroxine preparations as equivalent to branded preparations..."

"The question of a potential conflict of interest or appearance of conflict of interest does arise as related to these associations, which represent more than 4,600 clinical endocrinologists nationwide."


18 Replies

I read a paper called 'Does synthetic thyroxine suit everyone' by three doctors, one of which worked at my local hospital. I went to see him and he prescribed NDT but is now prevented from prescribing to any new patients by the hospital he works at!!


That is just criminal!


Was this the paper you were referring to? PR



Without a shadow of doubt for many patients like my husband my daughter and my grandaughter neither levothyroxine or Liothyronine t3 are any good at all

All 3 of them suffer horrendous joint pains from especially levothyroxine but almost as much on T3

The incredible difference Armour thyroid has made to my husband is obvious to anyone who knows him

The latest refusals by CCGs to refuse to fund NDT for such patients is culpable negligence condeming patients unable to tolerate levo or t3 to a life of misery and countless useless big pharma drugs attempting to treat the mountain of symptoms unless their finances allow them to cope with the cost of importing NDT and being fleeced by customs for 20% VAT plus another £8 to the Royal Mail to collect the same .

This situation has only occured thanks to the pig headed and blinkered actions of RCP,BTA and BTF

clearly these 3 must have a financial interest in the production of synthetic thyroid meds such that they are determined to lie and cheat thyroid patients of a good quality of life


It is interesting how it can run it families. Neither my mother nor my sister were able to tolerate Synthroid so when my turn came, I refused to even consider it. This is something science should be capable of figuring out. PR


While much of the article is perfectly sound, I struggle with the conclusion!


The history of levothyroxine sodium is one of great complexity and importance. While concerns remain regarding the subpotency of some brands of levothyroxine, consumers can be assured that the approved preparations are bioequivalent and interchangeable. Today, with FDA's ratings known, formulary decision-makers have the ability to make evidence-based, price-conscious decisions.

The loss of reference status by Synthroid was entirely of their own making - the makers failed to get their application in and approved first. Any person in the street would have assumed that their market share and overall dominance would have meant they would be ready with their application as soon as they were being accepted!

It would be good to have an equivalent article about the UK. I guess the MHRA report fulfils some aspects:




We do have to give the various owners of Synthroid credit for maintaining market dominance, apparently spreading the money around is a successful strategy. I missed your post on the MHRA article, I will go read it now. PR


Absolutely amazing they have maintained such dominance - though foul ups by the likes of Pfizer/Levoxyl certainly help them!

It was the MHRA article itself I was pointing towards - not any words I might have wittered! :-)



60% of ATA funding came from Boots (manufacturers of Synthroid). Who fund RCP, BTA & BTF?

I had always assumed bioidentical meant the drug performed identically to the thyroid gland when it actually means identical action of commpetitive drugs.


Boots are no longer owners of Synthroid. Not for many years.

Bioidentical means that the molecules are identical to those produced in the body. There are two ways in which this is slightly transgressed with levothyroxine. First, for practical reasons of stability and delivery, we get the sodium salt of levothyroxine. I suspect that this actually gets changed in the acidic environment of the stomach - but am not sure. Secondly, the level of hydration at the point of consumption will almost certainly be lower.

Once in the bloodstream, there is absolutely no way to tell apart molecules of levothyroxine that were produced in the thyroid from those that were taken by mouth.

Other substances that we take as medicines (whether or not hormones) are often not identical in any sense. A classic one mentioned several times recently is alfacalcidol - which is NOT vitamin D in any real sense, but has similar functionality to the "real" thing and seems to have specific advantages to those with kidney disease.

The interchangeability of medicines is usually called therapeutic equivalence.

If you wish to know who funds the RCP, BTA and BTF you can check out the charities commission website and the organisations' own websites, or contact them if necessary. I vaguely remember checking some of that out but so long ago I cannot remember and would not be sure the answer hasn't changed!



According to the article Boots were the owners when endocrinologists spammed the FDA about Synthroid. Thanks for the explanation about bioidentical medicines.


You are quite right - they were the owners then.


Lets face it, if you are on synthetic thyroxine the drug companies can have a field day as you are prescribed more and more useless drugs!!


I am prescribed nothing other than levothyroxine. It is NOT universal that people taking levothyroxine need to be/want to be/get prescribed anything else at all. Some actually feel pretty well without.



Levo is cheap rubbish and the majority of people that take it are very good at believing their doctors when they say 'It's not your thyroid' I know personally around 40 people on levo who rave about how great their doctors are then in the next breath complain about their symptoms! Personally I think that there should be a choice, levo doesn't work for me or for thousands of others.


Glynisrose, there is no question that Levothyroxine works just fine for some people and doesn't work well for others. The problem is that as patients we are not given a choice, we are only given one option. I am for whatever relieves a patients symptoms and returns them to good health. I don't care what it is, i.e. syn T4, Syn T4 + T3, NDT, NDT + T4, NDT + T3, raw glandulars, even ADs on a temporary basis if that helps. We need to fight for a patient's right to have any viable option open to them, not to restrict or limit a patient's options. There is no 'one size fits all' in the thyroid world. We must not let the anger we feel at our mistreatment and lost years end up restricting the options for other patients. It is more productive to educate those patients who haven't been adequately treated and still suffer symptoms that there are alternatives. PR

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Really? Who told you that? A doctor? As I said I know many people on levo and it doesn't work.


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