Has anyone noticed deficient B12 type symptoms ... - Thyroid UK

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Has anyone noticed deficient B12 type symptoms with T3 dosing?

Judithdalston profile image
13 Replies

I added T3 to my levothyroxin a year ago, after 14 years of low FT3, and poor conversion, and about 6 weeks ago went T3 only (50 rising to 75 mcg one night time dose daily). In Jan. 2019 active B12 was 196, but just before starting T3 was >300. I assume deficiency takes many months if not years, yet over the last 2 or so weeks noticed symptoms with tingling in feet, lower legs, arms, hands and bad vertigo ( have had symptoms like forgetting words for 3-4 years too). I noticed the other day that Slowdragon had mentioned low B12 type symptoms too taking T3, and gave up with large quantities. I am trying Dr. Lowe’s protocol for eleviating fibromyalgia, so don’t want to give it up...am I really B12 deficient in my cells, or is something else happening? Will it pass? Would B12 injections help?

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Judithdalston profile image
Judithdalston
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SlowDragon profile image
SlowDragonAdministrator

That's no quite what I said..... I have only ever had small, split dose T3

On 125mcg Levothyroxine my FT4 was always around 20 (range 12-22) and FT3 was about half way in range

Hashimoto's & Heterozygous DIO2 & gluten intolerant

T3 started in 2017, my Levothyroxine dose was dropped down from 125mcg to 100mcg when T3 was introduced. Initial T3 was 2 x 5mcg.

After 6 weeks and blood test, T3 was increased by endo to 20mcg (as 3 split doses 10mcg, 5mcg and 5mcg) and Levo dose remained at 100mcg FT4 had dropped to 16 (12-22 range)

At next test 12 weeks later my FT4 had dropped to 14 (12-22). I had started to get a lot of symptoms similar to years ago, before dose of Levothyroxine was increased high enough. Typically pins & needles, slight dizziness, numb feet etc.

I decided to increase Levothyroxine slowly. Initially to 112mcg. Retesting 10 weeks later. This stopped the FT4 dropping, but it hadn't gone up. Some improvements in symptoms

Increased again back to 125mcg, symptoms all slowly improve and completely resolved. Retesting again 10 weeks later, FT4 back to where suits me at 18-20

SeasideSusie also finds she needs FT4 in top 1/3 or 1/4 of range

Judithdalston profile image
Judithdalston in reply toSlowDragon

Thanks for replying, wasn’t really taking you name in vain! So you don’t think it is directly to do with B12, but FT4 related? I have had these symptoms before, eg when I was undermedicated on levo. 15 months ago...and had assumed it had gone as both upped the levo. but more particularly as improved ferritin, folate, vit D and B12 levels. These symptoms are exactly as ‘Sue’s study’ case story 2/3/2012 on main website, right down to forgetting words...which were attributed to low B12. Yet my Jan 2019 active B12 was 196, though had gone down by 50% or more in two months as started T3 with levo. combo. So I might have to give up Dr Lowe ‘s T3 only fibromyalgia regime but will wait a couple of weeks to retest bloods?

SlowDragon profile image
SlowDragonAdministrator in reply toJudithdalston

Yes, my B12 never dropped into anywhere near low range. I was taking one x Igennus B complex per day and had been for about 18 months

I suspect that, for me, low FT4 in some way interferes with B12, but doesn't reflect in B12 test results. Functional low B12 rather than actual low B12.

Since putting Levothyroxine up I have been able to cut Vitamin B complex to just half tablet per day. Might or might not be coincidental

People on NDT perhaps don't seem to have this issue with low FT4?

Judithdalston profile image
Judithdalston in reply toSlowDragon

Yes, perhaps some form of interference, as I think it unlikely to be low active B12 as I usually take B Complex, and more recently sublingual B12. I’ll do complete bloods in a few weeks, before a reappraisal of Thyroid ( and fibromyalgia) Snakes and Ladders.

nightingale-56 profile image
nightingale-56 in reply toSlowDragon

Just a thought, when my son had his Levo raised by 25 mcg to 100 mcg, his B12 doubled from 700 to 1500. No Endo or GP have commented on this though. Am hoping to bring this up at a meeting with GP in a couple of weeks time. Maybe this would be another way that we could tell if we were on an optimal dose of Levo.

SeasideSusie profile image
SeasideSusieRemembering

SeasideSusie also finds she needs FT4 in top 1/3 or 1/4 of range

That's right. Through trial and error I have found that I need both FT4 and FT3 around 75% through range.

Murphysmum profile image
Murphysmum

Yes!!

I am there. You commented on my post the other day, thank you. Slowdragon mentioned it to me too. I have exactly these symptoms at the moment, as I had when I was very undermedicated so I am assuming that my t3 and T4 levels are now too low, causing the symptoms.

It seems to be a balancing act that I, for one, am right at the start of 😩

Edited to say that every time I feel like this again, I wonder about going back to the gp and pushing for more B12/PA testing. Then I remember I’ve been here before and these particular symptoms have gone away at points.

Judithdalston profile image
Judithdalston in reply toMurphysmum

Yes adding or starting on T3 only is not an easy option. Bit more one step forward two steps back than using levo.only. A year on T3 and dropping down a snake again...need a few more ladders to get this pain, exhaustion etc sorted!

nightingale-56 profile image
nightingale-56

I have just been diagnosed with PA and had just begun to think that maybe it was to do with adding a small amount of T3 (6.25 mcg) over the past few years. At the beginning of February I ended up in A&E for numbness in feet, but the Doctor I saw, who was brilliant, said that I had a bad chest infection and she thought I also had PA. I have just completed loading doses and a fortnight later,symptoms are just beginning to return. GP has allowed me to have B12 injections once every 8 weeks, but I feel that this will not be enough in the long run, so have ordered extra B12 ampoules ready to self-inject if necessary. Not sure it really is to do with adding extra T3 as it seems to be well-known that auto-immune problems do not come alone. if you haven't already started to add B12 and B-Complex supplements, perhaps you could be tested for PA. Hope you find the answer soon.

SlowDragon profile image
SlowDragonAdministrator in reply tonightingale-56

What's your recent FT4 results ?

Did you reduce Levothyroxine when you added T3?

If so perhaps FT4 level is now too low

nightingale-56 profile image
nightingale-56 in reply toSlowDragon

I have recently changed to WP Thyroid (beginning of (February) and am to have another blood test tomorrow. couldn't wait in the beginning and has bloods done a fortnight after starting. My results then were TSH 0.57 (0.27 - 4.50), FT4 21.5 (12 - 22), FT3 5.9 (3.1 - 6.8), so although good, now the Levo and small amount of T3 has probably washed out of my system, this was not a true level, hence the bloods being done tomorrow (privately). I am feeling fairly well on only 1 grain of NDT and my blood glucose has come down to 5.5, with temperature starting at 36.5 rising to 36.9 at night. BP and pulse have also lowered to better levels. I am expecting the FT4 level to be lower, but the whole reason for going onto NDT was because I cannot tolerate Levo in UK since being changed from Goldshield Eltroxin to Mercury Pharma. still have skin condition this caused, but think this is lessening now. Might take a while yet to clear completely though.

Judithdalston profile image
Judithdalston in reply tonightingale-56

No I don’t think it is PA; early bloods before started supplementing everything suggested natural B12 highish, especially compared to poor ferritin etc. But making sure everything remained optimal I supplemented including B Complex with B12 and occasional , say weekly, sublingual B12. My active B12 had gone down in Jan 2019 but still above what had become newer higher range. So seems either high T3/ or / and low FT4 combo might be interfering with B12 some way, giving me symptoms like b12 deficiency...very odd.

nightingale-56 profile image
nightingale-56 in reply toJudithdalston

So glad your B12 appears to be good and do hope you find an answer to this soon.

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