Thyroid UK

Mercury Pharma question

Hello everyone

New here although have been lurking for a long time.

This may sound like a bizarre question but there is a method to my madness....

My GP was very against giving me a trial of T4 but when my antibodies came back high I went in armed with lots of information I have found on this great site and demanded a trial. This has taken me weeks to achieve and now I have been on the medication for about 7 weeks. During the time I was trying to convince him he kept spouting that it would be a placebo effect and that with my tsh results he wouldn't dream of giving me more than the starting dose anyway. I then came across a post by one of the members here but for the life of me I can't find again and it basically said that some GPs are giving patients fake medication. So you think you are taking levo but it actually has nothing in it. Now that has made me suspicious and I can't help but wonder how you would identify a fake pill.

So here is my question...if you are on a dose of 25 please could you tell me what is embossed on your pill? Mine says FW41. Is this right?

I know this sounds incredibly paranoid but I keep thinking that maybe if someone else on the same dose can confirm that their pills have the same writing I'll relax about it and stop obsessing.

My symptoms really haven't changed much but from all my reading I think it is possibly due to low dose and the fact that I probably have Hashimoto eventhough my doctor won't admit it. He won't budge and will not raise my dose.

My results pre-treatment were:


tsh : 2.40 (range of 0.4-5.5)

ft4 : 14.8 (range 10-19.8)

tpo: 1832(range 0-150)


tsh: 1.6

ft4: 16.1

tpo :870


tsh: 2.70

ft4: 14.2

tpo: 1565

Started 25mcg of levo

November (after 6 weeks of levo)

tsh: 3.12


tpo: 1689

After reading on these forums also asked for other tests

Ferratin: 10.6 (range 10-291) normal no action . Yeah right!!! I'm right at the bottom of it! So asked for supplements of those

B12: 356 (211-911) normal no action

Vitamin D 23 deficient - doctor prescribed 5000 units x day for 4 months

Folate 2.5 below range - again prescribed 5mg x day for 3 months

Also tested but I hadn't requested is Serum C reactive protein 4 (0.0-6) Need to look into this one as I have no idea what it is....

Any input would appreciated.

Thank you :)


18 Replies

Hi Pingu and welcome. I am taking Levo and use the 25mcg pills.have checked mine and they indeed do read the same as yours with the same markings.So hopefully they are pucker ones! It could well be tho with your other results really low that your problems are stemming from low Vit D ferritin folate etc and not soooo. Much directly from the thyroid,all these bits and minerals need to be optimal,if not that can give hypothyroid type symptoms.

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Second this. :) Your ferritin and and Vit D levels are horribly low and your body needs them higher to convert T4 to T3 effectively.


Thanks Jazzw. Yes they are horribly low aren't they? Hopefully it won't take long to raise them. I had come across the conversion thing that you mention and that is why I insisted again for testing. The one that really stuns me is the ferritin...I'm in range (by 0.6!!!) so yeah no problem there apparently. I just couldn't believe me ears and I think I actually laughed down the phone when the nurse read out the results. I said "surely those levels aren't ok?" she said " the doctor said they are fine and told me to tell you that you don't need supplements". I said I didn't agree so she put me on hold whilst she talked to him again...I got my supplements in the end ;)


What kind of iron tablets did you get prescribed i.e. what is the supplement name? What strength is it and how many times a day are you supposed to take it?

As well as your folate being too low I think your B12 is too low as well. Since you have so many deficiencies/low levels of nutrients your gut is obviously not working well.

One of the things that helps people with thyroid problems and high thyroid antibodies is a rigorously gluten-free diet. You can't be on a low-gluten diet, that won't work - you have to be ruthless in eliminating gluten.

I don't know if anyone has mentioned it, but having positive antibodies means you have Hashimoto's Thyroiditis or Hashimoto's Disease which is a cause of hypothyroidism - 90% of sufferers of hypothyroidism in the UK have Hashimoto's. In other parts of the world hypothyroidism can be caused by iodine deficiency. Some people have an under-performing thyroid as a result of pituitary or hypothalamus problems or for unknown reasons. In the UK the term "Hashimoto's Disease" is rarely used by the medical profession as far as I know - instead the term "autoimmune hypothyroidism" is the one I've seen mentioned mostly.

You may find this site helpful - the site owner (a sufferer herself) has also written books on the subject.

Good luck!


Hi Humanbean

Thank you for your reply. I have been given ferrous fumerate, I believe the dose is 210 or something like that. I'm not at home at the moment so don't have the bottle to hand. GP really reluctant to give it out though "you're in range dear" That is what he said!!!

Thank you for the links, I shall have a good read over the Christmas holidays. Work is super busy at this time of year so when evening comes all I want to do is crawl into bed and sleep. I had come to the conclusion about Hashimoto on my own as my doctor didn't mention it.

Thanks for wishing me luck...have a feeling I will need it!!



That iron supplement is the one I take. I take 3 a day, spread out. I also take 500mg - 1000mg vitamin C with each pill. (It depends what dose is on sale when I buy it.) The vitamin C helps to overcome the problem of constipation that people get with iron. It also helps the body to absorb the iron, and is good for the adrenal glands too. If you absorb the iron well you might get to a good level of ferritin in about 3 - 6 months. Iron should not be taken for prolonged periods without thorough testing because iron overload is dangerous and poisonous.


Hi Cupi

Thanks so much for helping me relax about this. GP's words had been playing on my mind and I had convinced myself they were fake pills. Silly aren't I? ;)

I agree that my symptoms could be caused by those low levels. I just wish he'd agreed to test them ages ago. I'll start all my supplements straight away and hopefully that will help with the symptoms I have been having.

Are my tpo antibodies really nothing to worry about? GP is so bloody dismissive. They won't cause you problems he says so I think he finally agreed to a low dose to get me to shut up.

Oh and thank you for explaining the CRP. Had no idea what the test was for.


No, you're not silly at all! Paranoia is a hypo symptom! lol I'm terribly paranoid when my levels are low.

A sign that your tablets are real is that your FT4 level has gone down since you started them, and your TSH has gone up. 25 mcg is too small a dose to help anyone. What it does is suppress the normal amount of effort your thyroid is still making, but doesn't give you enough to compensate.

For example, say your gland output was 40 mcg. You start taking your 25 mcg, the poor, tired gland says oh ho! can lie back and put my feet up now! And stops producing. However, the 25 mcg is not enough to replace the 40 you were getting, so you end up with a reduction of 15 mcg! 25 mcg is usually just a starting dose for little old ladies with heart problems!

That is why, as a general rule, bloods should be done 6 weeks after the initial dose, and the dose increased. But your doctor obviously doesn't know anything about thyroid because those antibodies definately mean you have Hashi's, so things aren't goingto go away by themselves, they're only going to get worse.

As usual, with a wonky gland, you have lots of nutritional deficiencies. Unfortunately, doctors know absolutely nothing about nutrition! I'm not surprised he said your iron was ok. Happens all the time because they don't know any better.

And that B12 definately needs increasing - should be about 900. But do take a B complex with your B12 suppliments because they all need to be kept in line. Also, 5 mcg of lithium could improve absorbtion.

Your magnesium is probably low, too. And zinc! It's like knocking down a line of dominos, when one goes down, so do the rest! And with any nutritional deficiency, there are bound to be symptoms. It can make you quite ill.

I would think it's time for a doctorectomy, because yours seems exceptionally ignorant. Any possibility of seeing another one?

Hugs, Grey

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Hi Grey

Thank you for your reply and the hugs...much appreciated and needed. This whole thing has made me feel so lonely and fed up. I just feel that there is complete ignorance in the uk when it comes to these antibodies and all the various nutritional deficiencies.

The explanation you gave me there really makes sense. I totally see what has happened and why my levels have got worse.

You are might be time to look for a different GP. Rural area so not much choice but might have a chat with a few friends and see if anyone recommends anyone in particular. Just feel like I'm banging my head against a brick wall. Guess I shouldn't complain too much as I managed to get my T4 prescription in the end!

My B12 didn't look too bad I thought. I guess it isn't then so will look at supplementing that one on my own.



Rest assured, it's not just in the UK! It's pretty much global!

Yes, you got your T4, now, you don't just have to hang on to it, but you have to get it increased quite a bit. I would imagine you would need at least 75, if not more. But impossible to guess at how much anyone is going to need in the end.

Your B12 is in range, yes, but the bottom of the range is too low. In Japan, they suppliment anything Under 800. Unfortunately, for doctors, anything in range is 'perfect'! They just have no idea!


Sorry forgot to add CRP is a measure of inflammation somewhere in the body,but your reading doesn't seem excessively high.


Mine doesn't say FW41, they say TX25. I don't think mine are correct.


Are your pills Wockhardt rather than Mercury Pharma? If they are, then TX25 is the right stuff - that's levothyroxine. :)


Quite right. Says so quite clearly on the PIL:



Won't you look at that!?!? I wish I had found that website weeks ago! It says it clearly

"...Each tablet is scored on one side and engraved on the other with FW41..."

Thanks so much Rod :D


Go here:

Type "levothyroxine" into the search box and search. You will see the Patient Information Leaflets for every UK levothyroxine product. Read them and they will tell you what appears on the tablets.

The GP gives you a prescription which says "levothyroxine sodium" and the dosage/number/etc.

You take it to a pharmacy.

The pharmacy dispenses what the prescription says.

I cannot see any believable way that the GP could ensure that some specific people get "real" product and others get the fake.

I can see that a GP might think that a low dose of levothyroxine would act like a placebo. Thinking it is too low to do anything significant. In fact, a very low dose can reduce the amount of thyroid hormone your own thyroid produces by an amount close to or more than the dose you are taking. You have to take enough that the sum of what you are taking and what your thyroid is still producing is bigger than where you started off.


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LOL crossed posted you I think.

Yes I agree...just me being paranoid and silly Rod. But I feel much better now knowing that others have the same and even better after reading that link.

Thank you :)


Thanks for responding so quickly - and positively.


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