Blood test advice required please: I've been on... - Thyroid UK

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Blood test advice required please

Rainbow100 profile image
8 Replies

I've been on NDT now for over 6 weeks and not feeling any better, still have very bad constipation, fatigue (worst in the morning), anxiety/depression, brain fog possibly a little worse. I started on 0.5 grain, increased by 0.5g every 2 weeks and now on 2.5g taken in one morning dose.

1) One issue I am confused about is that of Magnesium supplements, I have to take them with each meal, they do not work for me taken at night or before food etc. I have breakfast 1 hour after my NDT and I was under the impression that it was only calcium, vit D, iron and oestrogen that had to wait 4 hours after NDT dosing. Dr. Lowe only ever make reference to calcium interfering NDT absorption. Does anyone know for certain about how long you need to wait after taking NDT to take Mg ?

2) Which bloods should I get done ? My GP will only do TSH and FT4, I don't need the extra expense of private bloods but I will do them if necessary, it seems that FT3 is important and i've never had rT3/4 etc. What about Ferritin ?

How long before the blood test should I stop taking NDT ?

Previous bloods done in March '16 - TSH 3.15, antibodies <4 (>35 indicates Hashi's), FT3 4.1 pmol/L (3.9 - 6.7)

/ FT4 13.4 pmol/L (12 - 22), 25 OH VITAMIN D 94 nmol/L (50 - 140). Saliva adrenal test (March '15) normal.

I've also tried many times in the past taking very high doses Vit D, B12 (sublingual & oral), all bought from Dr. Myhills online and they made no difference, even when I stopped taking them.

Help me please ! P****d off, frustrated and all the rest :o(

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Rainbow100
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8 Replies
greygoose profile image
greygoose

You should leave 6 hours between your NDT and magnesium. It will interfere with absorption.

When you are on NDT, the only important number is the FT3. The TSH and FT4 will automatically be low because you are taking T3.

Leave 12 hours between your last dose of NDT and the test - but, if he's only going to test the TSH and the FT4, it's really not worth doing them at all. Try suggesting he forgets the TSH and FT4, and just does the FT3.

You should get your vit D and vit B12 tested, and try taking the right amounts. If you don't need them, obviously they aren't going to help. :)

Rainbow100 profile image
Rainbow100 in reply to greygoose

Thanks GG. What is your source of info re: Mg ?

greygoose profile image
greygoose in reply to Rainbow100

Sorry, don't have any links to give you. It's just something I read when I was looking for that same info myself - and I forgot to bookmark the page!!!!!!

Rainbow100 profile image
Rainbow100

btw, do I need to actually "fast" for a period before the test eg no food etc ? I'm certain I was not asked to do so on previous occasions.

Angel_of_the_North profile image
Angel_of_the_North in reply to Rainbow100

Yes. Don't eat between dinner the previous evening and the test (which should be as early in the morning as possible). Water only. If you are on meds that contain T3 (like NDT) it is imperative that you have a FT3 test. GP can usually order it by writing taking liothyronine (or T3) on the form. Not much point testing TSH as T3 "should" suppress it.

shaws profile image
shawsAdministrator in reply to Rainbow100

The advice is, to get the best possible outcome, in a test for thyroid hormones is to have the last dose of thyroid hormones approx 24 hours before and take them afterwards. It should be a fasting test also as the TSH may be affected and an unnecessary adjustment made by the GP..

humanbean profile image
humanbean

What kind of magnesium supplements do you take, and in what dosage?

Rainbow100 profile image
Rainbow100

I take Natural Vitality's Natural Calm which is "ionic mg citrate made from a blend of citric acid and and mg carbonate". I take approx 150-200mg 3 times a day with food. This dosing is just enough to maintain daily bowel regularity and I also take a 2g vit C (yes 2g not 200mg) and probiotics. This may sound excessive but thats how bad the constipation is.

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