What is manufactured 'Thyroxine' made off? - Thyroid UK

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What is manufactured 'Thyroxine' made off?

jaxnbreeze profile image
36 Replies

I think I read on this site that manufactured thyroxine is 60% iodine if this is the case what are the other ingredients? Thanks, Jax

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36 Replies
helvella profile image
helvellaAdministratorThyroid UK

It is not a case of it having "other ingredients" in that sense.

Water consists of molecules - and each molecule has one atom of oxygen and two of hydrogen. Often referred to as H2O.

Thyroxine consists of C15H11I4NO4 - which is a way of writing: fifteen atoms of carbon, eleven atoms of hydrogen, four atoms of iodine, one atom of nitrogen and four atoms of oxygen.

If you work it out in terms of the weights of each atom, iodine is 65.34% of thyroxine by weight

"Manufactured" levothyroxine simply has one atom of hydrogen replaced by one atom of sodium. (This is done for what seem sensible reasons such as stability and absorption.) Once absorbed into the bloodstream, the sodium atom has gone and the thyroxine molecules in our bloodstreams are the same as we make ourselves.

(The above is based on dry thyroxine and disregards any water content. This is how the potency of tablets is assessed and what appears on packets.)

Levothryoxine tablets have other ingredients. You can see what those other ingredients are in various thyroid hormone medicines by looking here:

thyroiduk.org.uk/tuk/treatm...

Rod

Clutter profile image
Clutter in reply to helvella

Did you study biochemistry, Rod? You have an impressive grip on this?

shaws profile image
shawsAdministrator in reply to Clutter

I would have asked the same question as you to Rod.

eeng profile image
eeng in reply to helvella

what an impressive answer!

veronicahoward profile image
veronicahoward in reply to helvella

Can you say where the iodine or the generic levothyroxine is sourced from? Is it derived from a porcine souce? Generic Levothyroxine seems to being giving lots of people on this site adverse reactions. It is not the same as Eltroxin which is still being manufactured by Customs in Sussex withdrawn by Amdipharma who hold the licence. I have a major legal enquiry into this.

APJ100 profile image
APJ100 in reply to helvella

With the correct ingredients and some basic laboratory equipment, how difficult would it be to manufacture some kind of basic thyroid hormone substitute? I ask because I would like to know if I would be able to survive an event that prevented access to the professionally manufactured medication.

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

Whilst it is usually described as a fairly simple process, there are many pitfalls.

A major one being the impurities that are likely to exist. These impurities have been a problem for all manufacturers. Unless you have a well-equipped modern lab, you are unlikely even to be able to detect these impurities - let alone remove them satisfactorily.

I offer one patent link - there are many others:

patents.google.com/patent/W...

Note: This is a patent for the process, not for levothyroxine itself.

And when you have created levothyroxine, and purified it, you need to dose with it. Producing accurate doses at the level of a few micrograms is a challenge in itself.

Imagine you put a small spoonful of levothyroxine into a kilogram of sugar, and then try to make sure the resulting mixture is very, very evenly distributed.

APJ100 profile image
APJ100 in reply to helvella

Thanks. Do you know if there are machines available that can measure TSH levels from a pin prick? It would presumably mean it would be possible to stockpile and take out-of-date Thyroid hormone substitute, and titrate the dose, even if it had decayed somewhat (not completely).

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

If you have several hundred thousand pounds and someone who is able to run it. (There might be analysers which are only tens of thousands of pounds.)

The tests like pregnancy tests which have been heavily promoted only say whether your result is under- or over-5. Frankly, so bad they should not be for sale.

It is one of my big hopes that we will end up with FT4, FT3 and TSH testable on a tiny device and which use a mobile phone for the computing/display requirements. Might happen but it isn't here yet, not as a validated and purchasable option. If it does appear, the cost might be too great for most of us. That is, add the cost of the device plus whatever consumables and it could well be cheaper to send samples to a lab.

APJ100 profile image
APJ100 in reply to helvella

Please could you keep us posted on progress with their development? At home testing seems to be necessary if you cannot access a supply of newly manufactured drug.

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

I already have posted about such things. But there has not been any meaningful progress in quite some time.

APJ100 profile image
APJ100 in reply to helvella

Actually, there are at-home TSH testing kits available: healthline.com/health/tsh-t...

tattybogle profile image
tattybogle in reply to APJ100

'at home TSH testing kit's available' ..Not quite ... . these are 'at home' blood sampling ' .. The blood is then set off to labs who do the actual testing on machines, and the lab then sends you the result .

The question related to whether there was a way you could actually do the testing yourself , totally DIY ...

APJ100 profile image
APJ100 in reply to tattybogle

That's true, I didn't see they were just at home sampling. Looks like I would just have to take increasingly old levothyroxine, increase the dose over time, and hope for the best.

tattybogle profile image
tattybogle in reply to APJ100

you don't really 'need' blood tests at all . if you know what the symptoms of overmedication , and under medication are for you (~ were are all a bit different ). thyroid conditions were managed perfectly well before anyone ever knew how to measure TSH.

signs and symptoms ~ heart rate / blood pressure ( 'pulse pressure ' ), frequency of bowel movements , weight gain/ loss . fine tremor in fingers/ or not . Temperature , etc etc etc .

APJ100 profile image
APJ100 in reply to tattybogle

That's good to know. Yes, I think I would be quite tuned in to monitor any symptoms. So the big question would be, at what rate does levothyroxine active ingredient decay?

tattybogle profile image
tattybogle in reply to APJ100

Don't know , but would also obviously depend how well you store it . keeping moisture out would be very important (unopened blister packs do this very well ).also temperature stability etc .. ( Levo doesn't really have an 'active' ingredient .. .. your body turns the T4 in to T3 which is the 'active' bit ... )

APJ100 profile image
APJ100 in reply to tattybogle

A lack of active ingredient may mean its real shelf life (not one published for regulatory purposes) is quite long for a blister pack.

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

But they are just collect blood at home and send off for analysis kits.

If the labs are operating, you will surely be able to get levothyroxine?

APJ100 profile image
APJ100 in reply to helvella

I'm thinking about a systemic collapse or something like that. The prognosis would not be good for someone on Thyroxine, like me.

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

I think labs would disappear very quickly.

The most available sources of thyroid hormone would be animals. But not necessarily the traditional sources (bovine, porcine, ovine) - other animals also produce thyroid hormone. Like fish. But I do not know how much and whether they are viable sources.

APJ100 profile image
APJ100 in reply to helvella

Yes, fish would certainly be more iodine rich.

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

Freshwater fish wouldn't be!

APJ100 profile image
APJ100 in reply to helvella

True!

APJ100 profile image
APJ100 in reply to helvella

Do you know if there is any data on the rate of decay of levothyroxine active ingredient over years?

helvella profile image
helvellaAdministratorThyroid UK in reply to APJ100

As manufactured, UK levothyroxine must be within the range 90 to 105% of claimed potency.

It must also remain within that range up to expiry date - so long as kept in reasonable condtions.

I think it reasonable to assume that a batch which was 100% at manufacture might well be at 95% two years later. And that deterioration might continue at a similar rate indefinitely. So a rule of thumb of somewhere in the range 5% or 5 micrograms in a 100 microgram tablet, every two years, seems feasible.

But, at the same time, the level of unwanted and possibly harmful breakdown products will increase.

APJ100 profile image
APJ100 in reply to helvella

I would just have to hope the breakdown products were not too harmful, since the alternative would be certain death!

tattybogle profile image
tattybogle in reply to APJ100

Hypothyroidism is a very very slow cause of death . . just involves an awful lot of struggling to function effectively along the way . In a ;systematic collapse .. i imagine you would be dead//feeling crap from 'something else' that could no longer be treated as effectively as it is currently , long before hypothyroidism was the biggest problem you had . ... not saying you'd be having any fun , but just that i think you'd have bigger problems than 'optimal thyroid medication'

for example ,you could die very quickly from anything from a broken leg. to cancer.

APJ100 profile image
APJ100 in reply to tattybogle

I don't think I have any natural thyroid function, because I had my thyroid ablated with radio-iodine. Without thyroid hormone replacement, I think I would be a gonner sooner rather than later.

tattybogle profile image
tattybogle in reply to APJ100

Ah . .. in that case , 'sooner' is more likely . best have a big cupboard full of Levo then .. and start learning how to keep pigs (or something else with a thyroid) for when you run out / it doesn't work anymore / somebody evicts you and steals the contents of your cupboard / flood washes your cupboard away / fire burns it down.

I think it's a safe bet that well stored Levo would still 'work' for many years beyond use by date .. dosing would just have to be a become a bit more 'suck it and see' over time .

APJ100 profile image
APJ100 in reply to tattybogle

Yep, a massive stockpile, together with symptom self-monitoring, would seem to be the only feasible option.

helvella profile image
helvellaAdministratorThyroid UK

Why do you think that is so?

Rod

susymac profile image
susymac

I was under the impression that ALL pharmaceuticals used petroleum (as methanol, ethyl acetate etc) as the organic molecules are water soluble and need to be collected with an oil based substance which is then taken back out of the process. Chemistry was never my strong point,(I was diabolical at it), but Im sure even the natural products use petroleum products at a base level

jaxnbreeze profile image
jaxnbreeze

Thanks Rod -Am right then in thinking that the other ingredients are needed to allow the iodine to work but are there any other compounds in the tablets that exhance thyroid function? Did I read that someone mentioned L-tyrosine and carnitine are also in the tablets although they are not on the list of ingredients? Both these compounds plus iodine are in Nutri Thyro. Complex.

helvella profile image
helvellaAdministratorThyroid UK in reply to jaxnbreeze

As I see it, thyroxine is like a key. It needs to be as it is in order to work. I don't see it as a way of making iodine work - just that some of the notches of the key happen to be iodine atoms.

The other ingredients of levothyroxine tablets are there to bulk out the product, to stabilise, to ensure disintegration when taken, to allow the factory process to run smoothly, to ensure even distribution so that each tablet contain the same amount, and all the other things that are important.

To the best of my knowledge, not one other substance is there in order to change the effect of levothyroxine itself.

Tyrosine and iodine are used in the working thyroid to make thyroid hormone. If there is an insufficiency of either of them, that could have an impact on thyroid hormone manufacture within the thyroid. What effect they have when there isn't an insufficiency, I do not know.

Rod

anjh-blue profile image
anjh-blue

Rod what kind of reaction/symptoms does your husband & co suffer with from taking synthetic thyroid?

My daughter has tummy pains, head aches, swollen tummy/eyes etc?

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