blood test and T3 dose

[greenm]

Hi, had a recent blood test, results below. I thought my T3 would have been higher, I am on 62.5 mcg T3 only, not able to tolerate T4 as I make too much rT3 and self-medicate. Just wondering if I left too much time in between my last dose and the time of blood test, was about 15 hours. Last couple of months I have been feeling tired and muscle aches, also just started combined HRT - could this have an effect?

I have been thinking of adding in a bit more T3 to see if that helps but read somewhere that around 60 mcg someone should be fully replaced? I have an endo appnt next week as my new GP was a bit concerned I was "going it alone" . So my question is are my T3 results good and is it usual for someone to have to add in a little extra T3 for a while or indefinately. I've been on T3 only now 18 mths, thyroidectomy in 2003- Graves disease. Any comments/advice would be appreciated. thank you.

Results:

CRP HS 2.36mg/L (range <5)

Ferritin 46.60 ug/L (range 13-150)

Folate -Serum 11.7 ug/L (range >3.89)

Vitamin B12-Active >150pmol/L (range >37.5)

Vitamin D 130.00 nmol/L (range 50-175)

TSH 0.02 mIU/L (range 0.27-4.2)

Free T3 4.68 pmol/L (range 3.1 -6.8)

Free thyroxine 0.500 pmol/L (range 12-22)

Thyroglobulin antibodies <10 kIU/L (range <115)

Thyroid peroxidase antibodies <9.00 kIU/L (range<34)

[greenm]

forgot to mention, have been putting on weight , 1/2 stone over 2 months

[greygoose in reply to greenm]

I'm not surprised you've been putting on weight. Your FT3 is not even mid-range. That could be partially explained by leaving too long between the last dose and the blood draw, but it was only about 3 hours, so shouldn't have made that much difference. How do you take your T3? On an empty stomach, leaving at least an hour before eating, etc. just like levo?

not able to tolerate T4 as I make too much rT3 and self-medicate.

That is not, actually, a good reason for going T3 only. There are plenty of good reasons, but that's not one of them, because rT3 is not a problem, in or of itself. It doesn't do anything, it is inert and only stays in the system for a couple of hours before being converted into T2.

There are many, many reasons for high rT3, and only one of them has anything to do with thyroid. And, that is when your FT4 is too high. The solution, therefore - should a solution be necessary - is to lower the dose of levo, not stop it altogether. I'm not saying you shouldn't be on T3 only, but that your reason for doing that doesn't hold water.

read somewhere that around 60 mcg someone should be fully replaced?

Whoever wrote that was being silly! You cannot possibly say that everyone should be fully replaced on any given dose, because we all react so differently to it, and have different levels of absorption, etc. There are so many, many variables that will affect how much we need. We're not machines, we're flesh and blood, and we're all different. So, if you need to increase your dose, increase it - but make sure you're taking it correctly first. Myself, I take 75 mcg, and that is the dose I absolutely need - I've checked it several times by increasing or decreasing it a little, and always have to come back to 75.

I don't know much about HRT, I've never been on it, but I believe it is normal to need to increase your dose of thyroid hormone a little when taking it.

[greenm in reply to greygoose]

Thank you for your great advice, I did think the T3 was a bit low, I will increase it gradually and see if symptoms improve. Yes I was certainly on alot of levo for a long time but when I reduced just felt so awful so was on that roundabout of increasing and decreasing every few months as advised by the GP and that went on for years resulting in high Rt3. Had my thyroid genes tested DI01 snp, the clearance gene negatively impacted so not being able to clear excess rT3 adequately. I do feel so much better on the T3 only 😀😃

[greygoose in reply to greenm]

I'm afraid that's really not how rT3 works. It's perfectly normal to always have some rT3 in the system. A certain percentage of T4 will always convert to rT3. But, it clears itself with no problem - as i said, it ony stays in the system for about two hours before converting to T2. It's the body's system for recycling iodine, and preventing people from going hyper, and all sorts of other useful things. rT3 is not a bad thing, it's not the enemy. And, it certainly doesn't cause any problems - it's the result of certain problems, not the cause. So, it was really, really nothing to worry about, and not a reason for going T3 only.

However, it sounds as if you needed some T3 because you had a conversion problem - many reasons for poor conversion, but nothing to do with rT3. And the DIO1 snp certainly has nothing to do with 'clearing' rT3. As I said, it 'clears' itself.

[greenm in reply to greygoose]

thanks for explaining greygoose, it's so confusing how it all works and so much info out there - good and bad, this forum is great for getting advice and learning more 😀

[greygoose in reply to greenm]

You're welcome.

[tattybogle]

If you're really interested in deiodinases , (and are not suffering from brain fog !) see this post healthunlocked.com/thyroidu... understand how the deiodinases work

I think you're both right... rT3 is not the big problem people think it is AND there a connection between DIO1 /rT3

D1 as well as D2 and D3 have a role in turning rT3 into T2 .

it's complicated , but there's a good picture on that post which helps me .. otherwise i can never remember which deiodinase does what.

[greenm in reply to tattybogle]

thank you I will take a look at that 😀

[jimh111]

Possibly too long between taking your L-T3 and taking blood. What times of day do you take your L-T3 and what time was the blood taken?