Diagnosis and treatment of B12 deficiency or PA - Thyroid UK

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Diagnosis and treatment of B12 deficiency or PA


I know I keep harping on about B12 but I can't stop myself as it seems to be so often connected to people with thyroid conditions. So, this may be helpful to those trying to convince the unconvincable or self diagnose or treat:


Although this mentions later on in the article about the more accurate Active B12 test and clearly states diagnosis should not just be based on blood test results, it does still go into detail about the levels and what they mean. I think this is a little misleading because it could still make people think they do not have PA or a B12 deficiency or it is only moderate because of the low levels quoted. The web site does though mention what needs to change in the diagnosis and treatment:


26 Replies

Please keep "harping on" Edit - I'm just as convinced as you that B12 deficiency plays an important role in the development and treatment of thyroid conditions, and am currently in the process of trying to get mine adequately treated....even diagnosed would be good.

I've been in touch with St Thomas and Guys hospital about their 'active' B12 test and have just found out that if you can get a referral from your GP and are prepared to pay £18 (plus £12 transport) they will test a blood sample for you - alternatively you can save the £12 by making an appointment to have the blood taken at the hospital.

Lolalois in reply to Hidden

Sorry to sound ill informed, but what's an active b12 test? Mine is low and I've started sub linguals, but dr says its not too bad (result 206)!

tingles in reply to Lolalois

imho that is far far too low. mine was 220 and I had been for 5 years. toes and finger numbness, brain turning to mush! feel so much better now my levels are really high. i self treat, started off on sublinguals and now inject. hope you feel better soon x

Lolalois in reply to tingles

Sorry to bother you again, but how long did it take for you to feel better once you started supplements? It's been a couple of weeks for me and I'm feeling better but not fully resolved yet. Thanks x

bluepettals2 in reply to Hidden

sue f , are you saying that we only need a letter from gp and we, the patient pays the £18 at the hospital?

Hidden in reply to bluepettals2

That's my understanding pettals, but you could contact St Thomas and Guys for further details. Ignore my reference to Guys & St Barts - I'm getting my saints mixed up - it really is St Thomas and Guys.

nobodysdriving in reply to Hidden

I will ask them too, I have my active B12 done at this hospital :)

though now I have given up testing it as I am always over the range with my weekly sub-cut injections of B12 :D

Hidden in reply to nobodysdriving

Do you do your own injections NBD? If so, how did you go about learning how to do it and where do you get your needles/ampoules?

If your GP surgery does it, how did you swing it?

nobodysdriving in reply to Hidden

I do my own injections as injecting is part of my job anyway so I am used to it :D ;)

however it is VERY VERY easy to learn how to inject, if you have someone in real life to help it's a bonus but you can even learn over the internet! :D

My GP would NEVER in a million years give me B12 supplies to self inject every 5 to 7 days, I have the support of my private doctor, dr M, who has helped me establish a B12 regime which was right for me :)

I still get my ONE ampoule of B12 from the GP every 12 weeks though, I won't let them save the 69pence it costs them! AH! LOL

dr M teaches patients how to self inject if they want to.

hi there nobody, i sub cut too, but only once every 2 months or so, can you tell me how you feel with a weekly one, what did the active b12 come up with? were you "over"?

Hi there Tanny

yes I am 'over' lately with my B12 that is why I don't bother doing it anymore. The range is up to 128 and I come out with >128 :D

My private doctor told me to self inject daily for at least a month then to 'titrate' according to how I felt.

At first I chose weekly as I could not tell and knew already that with 2 monthly it was not enough, but lately I have learnt to recognise when my body needs more....

recently I forgot to inject on the saturday, I always inject on saturdays and by Tuesday I was very tired by 12pm almost falling asleep at my desk at work LOL

so I then injected on the wednesday evening and by thursday my tiredness was 'magically' gone :D

I know now that 9 days is too long for me to go without it and am listening carefully to my body to see if I need it more often than weekly :)

My doctor is happy for me to have it as often as I need to :)

ps up to 128 is the 'active B12' range, the 'new test' we talk about here in this thread

thanks for replying, good for you! my latest blood test was >1500, but am not concerned as feel soooo much better. Thank god for B12 thats all I can say. Do you use the hydoxycobalamin?

yes Tanny hydroxocobalamin :) x

waveylines in reply to Hidden

Thank you Sue for this info.

I have been to my GP today as i am feeling soooo poorly despite being well treated on NDT and using CT3M and supplementing with the B's and folate. I have just slept and slept and slept for the last four days and to be honest haven't felt well over the last year -noting a gradual decline with little peaks of improvement before slumping further. i asked my GP if this was normal for treated hypothyroidism -he said oh no definitely not! lol Have to laugh at this!

My GP was not at all phased and was straight into talking about Celiacs and B12 -PA ( was a little stunned!) and said as he took a gallon of blood he was testing for everything (no idea what that means! as he would not expand on what he meant when I asked). I told him that my B12 level in my blood is probably flooded as have been supplementing with sublingual b12 so doubt that test would be helpful -but he seemed to think it would be still a good idea to test -and said the size of the red cells would tell him if it is PA ( this is not strictly true as it is a very late symptom but was too exhausted to dispute). my blood looked a lovey deep red so doubt i am anaemic. Only been today but he said most of the results would be back by Friday -Coeliacs next week.

We had a little discussion about my autoimmune weakness - as I have 2 autoimmune conditions. he said none of us get away without something affecting us -very prosaic! And in the same breath when i asked him what I should do about work -he said -well you don't have a medical condition but you can self certificate if you need to.....So there we go i have 2 diagnosed autoimmune diseases (and maybe developing another ) but I don't have a medical condition......the logic of that left me speechless! but to be fare we had to pack all of this in the 10minute window allowed -so it would have taken more time if my medical conditions that do exist were allowed to exist with regards to work......!!!

I thought I will ask him to refer me for the Active B12 test -so Sue you have saved me ringing St Thomas's up. :) xx


Don't apologise - we're all more or less ill-informed because we tend to believe what a doctor tells us.

Your B12 may well be within your lab's reference range, but right at the very bottom of it. The optimal level is around 800 pg/ml, and it would seem that not all of what is swishing around in your blood is bio-available (i.e. can be used by your body at cellular level). The 'active' B12 test has been developed by Guys & St Barts Hospital and gives a more accurate result than the test offered by GPs. Take a look at this:


I've been on sub-linguals for some months and they have helped up to a point, but I seem not to be able to sustain the improvement. Do post on here how you get on with them.

waveylines in reply to Hidden

Thanks Sue -I will. get my first batch of blood test result back tomorrow -really quick! i want it to be a quick and easy diagnosis but i know this is extremely unlikely! Martyn of the PA Society says it can take up to 5 years......sigh....the similarities between getting proper diagnosis/treatment of PA or b12 deficiency are shockingly similar to thyroid disorders......lol

it has been recommended to me that you should take extra folate and make sure you are eating plenty of potassium (bananas -no really to eat i mean) to maximise absorption. I don't think i am taking enough b12 though -seems it should be 5000mcg tablets -am only on the 1000mcg twice daily.

Thanks for the link -oh hear i didn't realise you had to attend St Thomas hospital to do the test -I live in Sheffield so it would be quite a trek. I hear they are rolling out the Active B12 nationwide at private hospitals in the next few months....or I make the one trip to London! xx

Hidden in reply to waveylines

You don't have to go to London Waveylines - if you email them they'll explain the procedure and cost for sending your sample to them.

I'm currently taking 2 x 5000 mcg sublingually, plus 400mcg folic acid....and half a big banana with my breakfast!



waveylines in reply to Hidden

Oh thanks Sue -that has cheered me up :) knowing i can just send it to them...will email them for details.

Still feeling rubbish but I did make it out to the supermarket for a shop today -wiped me out after though. I really haven'y got very far with my Xmas preparation this year....lol!!

hello edit, and girls, yes keep harping on---- i am more than convinced this is part of my problem, i have read that link you left, and more convinced than ever, i asked my doctor today,-- armed with a print out from gsts--explaining that only a percentage is available for the cells, and asked for the test.... reply was...... she had not heard of the active b12 test--- and then went on the computer and said-- BUT Y OU HAVE ENOUGH B12 IN YOUR BLOOD STREAM! she gave me back the printout saying well you will have to ask your endo if he thinks its necessary as you HAVE ENOUGH IN YOUR BLOOD STREAM!--- I ASKED FOR A TRIAL OF B12 given that i am so tired, so fatiqued, very very dry skin, and so much hair loss, even tho i am on t3, plus pcos plus kidney impairment, degen spine--, reply was-- CERTAINLY NOT!--- YOU HAVE ENOUGH IN YOUR BLOOD STREAM!.. SO her ei am very all these symptoms an dso much hair loss.. and so very very pissed off.

Hi pettals so sorry to hear this -clearly she did not listen! Sigh -poor you.....did she realise she wouldn't have to pay for it?

I think you probably know this already as I think you are a member of the PA Society -but the Chairman, Martyn, has emailed out (or is it on their site -confusion confusion..memory defunct..doh) that they hope to shortly roll out access to Active b12 test privately at the Nuffield Hospitals for which you won't need your GP consent :)..... Big Hugs xx

wakeham in reply to waveylines

Hi everyone

reading all the info about your B12 very interesting,can you help me?my test results

B12 298 (150 -900)

Serum folate <24.8 (3.1 -19.19)

Serum Ferritin 24 (11 -307 )

R/blood cell distribution width LO 11% (12 -16 )

RBCs LO 3.8 10*12/L (4.0 -5.8 )

My GP said I'm in range some of these results I don't what they mean,I thought that B12 was low so have started B-Complex sublingual liquid but am I doing right thing please.

Regasrds to all wakeham.

Hi wakeham-I would have a look on the B12 site that tops this blog -it is really good. i would also go on the PA site. What is your GP going to do? Anything? if not I would ask fi you cna have the Active vitamin B12 test - see Sue F's post -you will need a letter from your GP. This will show how much b12 is active in your tissues - muhc more reliable test. It would seem though that you b12 serum is on the low side so you could do with supplementing. personally i would look at some B12 seperately as well the B complex.

I am not good on interpreting the other tests am afraid ( new to this myself) so if you don't get a response I would post on the pernicious Anemia forum at health unblock -you just click on my communities and ask to search other communities and you will find it. Sorry I can't be of more help. xx






wakeham in reply to Hidden

Thank you Heather14 Regards wakeham.


this explains the complexity and why our doctors are no good at helping us

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