Evening! I’ve been on 2g of NDT (ERFA) since July- not had a TFT done since March and before I started NDT. Well I’ve been feeling more and more hypo last few weeks- symptoms have been creeping up, and I’ve gained a stone in a month. Went to GP yesterday about my lower back pain and mentioned I’d not been feeling great- he ordered some blood tests. Had them this morning after having no meds since yesterday morning. The results are in- and they’re dire!
T4- 11.4 pmol/L
Normal range 12-22
Serum free T3 level- 3.8 pmol/L
Normal range
3.1 - 6.8
Serum TSH level 0.55 mu/L
Normal range
0.27 - 4.20
Now I’m aware that t4 drops when on NDT, but my T3 is right down the bottom & my T4 & T3 are lower then I’ve ever seen, but my TSH is suppressed.
What are your thoughts? And pretty sure my GP is going to recommend taking levo again- does anyone use both? I’m not sure I’m going to keep using to NDT really as I’ll have to go up a dose and obviously need to pay more for it... but I’d like to finish the ones I’ve got...
Tia x
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Melodica8
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he ordered some blood tests. Had them this morning after having no meds since yesterday morning
In which case you have false low results for FT4 and FT3. When taking NDT (or T3) we take last dose 8-12 hours before the blood draw (24 hours is for Levo only).
TSH often is very low or suppressed when taking NDT or T3, it's the T3 that does this.
It's likely that you could be undermedicated considering that you have symptoms and have gained weight, but you'll only know that if you repeat the test with the right time gap between last dose of NDT and blood draw.
Arghh it gets so confusing! 😩 so what do I say to the GP?! The thing is even before I was on levo my T4 wasn’t that low. (I saw a private endo who diagnosed me on symptoms and low end T4/rising TSH but still within range) I’ll have to see what the GP says I guess. What is the levo equivalent of 2 grams?
Do you want to go back on Levo? How do you normally feel on NDT compared to how you felt when on Levo?
If you want to stay on NDT then does your GP know how to interpret blood tests when taking it, they're interpreted differently from when taking Levo.
If you want to stay on NDT you can point out your below range FT4 and low in range FT3 and say that considering your hormone levels are so low and that you have symptoms and weight gain then it suggests you are undermedicated and could you have an increase in dose.
I’m not sure I’m going to keep using to NDT really as I’ll have to go up a dose and obviously need to pay more for it
Are you getting your NDT on private prescription then and not the NHS?
What is the levo equivalent of 2 grams?
If you are taking the 2 grain tablets then those contain 73 mcg of T4 and 17 mcg of T3. T3 is roughly equal to 3-4 times T4 so the 17mcg of T3 is approximatlely 51-68mcg T4. So 2 grains of Erfa is roughly the equivalent of between 124 and 141mcg T4. But if you need the T3 (if you have poor conversion of T4 to T3) then you probably wont do well on Levo only.
Could this be why you're having symptoms/weight gain:
CANADA’S “THYROID” aka ERFA, formerly by Pfizer and is now by Erfa. Note: beginning around May 2014 and continuing to today, many patients have reported Erfa was now causing a return of hypothyroid symptoms. Erfa denies a change, but there are too many negative reports from some patients now to think there hasn’t been a change, somehow.
Yes paying privately for NDT- I didn’t think you could get it on NHS? I’m sure my endo would be happy to up the dosage- but he’ll probably want to see me (more money!) and then will have to pay for higher dose of NDT. I went on to NDT as my weight was still creeping on. Tbh I think my endo is very happy to throw drugs at me but hasn’t really investigated properly. I was on 50mg of levo, my t4 went up to about 16- so went onto 75mg & my t4 went over, I felt jittery and horrid but my t3 was in range. So I don’t know what’s going on. I never had a b/t for reverse T3 either. Felt better generally on NDT but didn’t feel too bad on levo. I guess I don’t convert too well.
The GP’s I’ve seen didn’t even know what NDT was... 🙄 I’m actually taking two half grains twice a day as the pharmacy has been having difficulties getting the 1 & 2 grains. But presumably that should’t make any difference?!
Thanks for the link- I’ve spent most of the evening devouring information. It’s such a good website. One of the things I’m intrigued by is that NDT doesn’t always work that well if you’ve got cortisol problems. My weight gain is classic cortisol- all around my tummy. Slim arms and legs. When I last had my cortisol checked it was within range but right near the top. I dunno. I just want someone to actually listen to me properly and investigate- which is why I went private in the first place! 😒
NDT is not licensed in the UK although there are some patients prescribed it on the NHS. I expect many are from prescrptions first issued quite a few years ago as it's uncommon to hear of new prescriptions being given on the NHS, most GPs have never heard of it.
You'd need to post full results with reference ranges for TSH, FT4 and FT3 so that we can see what your conversion was like when on Levo only. When FT4 went over range, where in range was FT3? That's what will tell us about conversion.
I wouldn't worry about testing rT3. If the result came back high you won't know the reason and there are many, many reasons for high rT3 that aren't connected to the thyroid.
If you look at the link I gave about Erfa, it gives the hormone content of the different dose tablets.
Half grain tablets contain 18mcg T4 and 4mcg T3 so taking 4 x 1/2 grains = 72mcg T4 and 16mcg T3, a touch less than 1 x 2 grain tablet.
If you decided to go back on Levo, would your NHS GP prescribe it? Depending on what your conversion was like on Levo only before, you may need some T3 and that's difficult to get on the NHS.
When did you check your cortisol? If it was some time ago it might be worth doing a 24 hour saliva adrenal test for cortisol plus DHEA with Regenerus or Genova Diagnostics (details on ThyroidUK's main website).
Those results show that you needed a high FT4 to produce a reasonable amount of FT3 - your FT3 was 59% through range.
Although your ferritin was fine, your Vit D was way too low and your B12 was also very low, many people with B12 in the 300s have been found to need B12 injections. I have just found the post where you listed those results, unfortunately I didn't see it at the time or I would have commented, and none of the other replies mentioned that they needed addressing.
Nutrient levels need to be optimal for thyroid hormone to work properly and good conversion. I expect if your levels are still poor then this may be causing you problems. If you don't have up to date results for all of them then if you can manage it I would repeat the tests now, either with your GP or with Medichecks or Blue Horizon. You need current results for
Thank you again- yes I knew my vit D was low- although after a summer of sun and holiday in the med I’m hopeful that’s improved! And my GP mentioned my B12 was a bit on the low side but just to eat more red meat... the same GP who I normally hold in very high regard has said no action required on my TFT’s. I’m quite astounded tbh! They’ve accepted my endo’s diagnosis and I had been getting levo on the NHS. But I was only on 50Mg and 75mg when they thought I was overmedicated.
I’m going to look at cortisol salvia test on medichecks again, so will look at the vit d & b12 etc too
I’m going to look at cortisol salvia test on medichecks again
The Medichecks test is not a lot of good. It tests only cortisol and we need cortisol plus DHEA tested. They have zero as the bottom of the range for two of their samples and if anyone did actually have a level of zero I doubt they'd be walking around. They also use <1.5 for their bedtime sample rather than an actual result if it's below 1.5, so that can't possibly tell us where within the range of 0-2 it falls (I think the top of the range is 2 for the bedtime sample).
For a proper test of cortisol plus DHEA with proper reference ranges and a graphic of where you fall within the normal curve then consider either Regenerus or Genova Diagnostics, details on ThyroidUK's main website here:
Fantastic, thank you for that, that’s a good recommendation.
Can I please ask you something else? As you seem very knowledgable! I feel certain my Dad & Daughter are hypo- both symptomatic and both have lower end or out of range t4, rising TSH but within range (my daughter’s was 3.4 ref range as above) but adequate t3 (around 5, ref range same as above) My uncle (dad’s brother) is hypo. Can you shed any light on this? I’ve posted on both of them before...
It's very likely, with family history, that both are on the way to hypothyroidism. All you can do is keep an eye on levels. The NHS wont diagnose hypothyroidism until TSH is over range, often they wait until it reaches 10. If thyroid antibodies are present with an over range TSH that hasn't reached 10 then an enlightened doctor might start treatment.
If FT4 is below range with a normal, low or slightly elevated TSH then that can suggest Central Hypothyroidism which is where the problems lies with the pituitary (Secodary Hypothyroidism) or the hypothalamus (Tertiary Hypothyroidism).
Central Hypothyroidism is not as common as Primary Hypothyroidism or Autoimmune Thyroid Disease (Hashimoto's) and many doctors have never heard of it.
Right... is there a link with that and Cushings/high cortisol? My daughter has always been large- even as a child, didn’t matter how healthily she ate, she piles on weight. She has a buffalo hump and loads of stretch marks, and is very sluggish. It’s so frustrating as I don’t want to be like a paranoid hypochondriac mum but I feel sure something isn’t right...
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