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Pernicious Anaemia Society
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Help please - B12 deficiency?

Hi all,

First of all I want to say thank you for all that I already learned from this forum.

I am not diagnosed with PA, but I have hypothyroidism and on Levothyroxine for the last 17 years (current dose 150). During my recent GP appointment I was told I have low iron and should take iron tablets. I told my GP that these give me stomach issues and I will eat more iron-rich foods instead, and he was happy with that.

Few days later I went back to my GP practice and asked for my blood results. I found that my iron was actually much lower than I expected 5umol/L (range 5-33umol/L). My results also showed: transferrin 2.71 g/L (range 2.15-3.8), folate 16.7 ng/ml (range 5.4-24), ferritin 55ug/L (range 10-291), iron saturation 8% (range 15-50), and serum vitB 308 ng/L (range 180-910). Also, I recently had private vit D3 done which was 23.8 ng/ml (normal is >= 30).

I started reading HealthUnlocked to learn if my symptoms are due to low iron, and I realised that it may actually be functional B12 deficiency. Symptoms include: extreme fatigue (waking up tired with muscle aches, tiredness increase over time and peaks at about 3pm, some days have to lock myself in the ladies room and close my eyes for 5min or I'm unable to cope at work), general muscle weakness (struggle to carry my 10months old for more than few minutes, can't carry him up the stairs and if there is nobody to help and I have to do it, then I'm breathless and have burning leg muscles after climbing to first floor), numbness/tingling in fingers of both hands, balance problems, visual disturbances, forgetfulness, sleep disturbances, history of depression, irritability and mood swings, skin hypo-pigmentation and had real trouble getting pregnant until supplemented vit B12 by chance after reading somewhere that it helps(I stopped supplement as soon as I got pregnant though as I didn't know the impact on pregnancy and was scared to self-medicate).

Note that I may actually have absorption issue since both iron and vitD are deficient and B12 is low as well.

My question is - with these symptoms but "normal" serum B12, is there any point asking GP about B12 injections or should I just supplement myself? Did anybody get their GP to prescribe injection with serum level around 300? And if supplementing, then how much and for how long before asking to check blood again?

Thank you so much for any advice.

5 Replies

Hi moniacho there would be no harm in asking your doctor to give you a trial of B12 injections in accordance with the N.I.C.E guidelines at the same time as asking to have him check your Folate level as this and B12 help your iron to make healthy red blood cells.

Your thyroid problems put you at risk of developing a B12 deficiency and I think your doctor would know this - or maybe not.

Despite your B12 level being classed as "Normal" it is at the lower end of the scale and the British Society for Haematology say "In the presence of discordance between the test result and strong clinical features of deficiency, treatment should not be delayed to avoid neurological impairment." or in other words if despite your "Normal" B12 levels if you are having neurological symptoms treatment should be started immediately.

I am not medically trained but there are others on here who will be able to give you good advice on supplementation should it come to that but hopefully your doctor will "pick up the ball and run with it"

1 like

Thank you clivealive. Maybe it is worh giving it a try then. I can always supplement myself later if he says no.


Serum B12 is a problem test if used as a single measure - it will miss 25% of people who are B12 deficient and pick up 5% who aren't. Evaluating symptoms is important. This may include macrocytosis but macrocytosis isn't present in around 25% of those presenting with B12 deficiency and if you have neurological symptoms recommended practice in the UK is to treat with injections if there is a discordance between symptoms and results to avoid the risk of permanent damage.

suggest you put together a list of your symptoms, along with the above stats - which come from the BCSH standards for treatment of cobalamin and folate deficiencies.

BCSH = British Council for standards in haematology.



It can be helpful to put things in writing to your GP before going to see them.

It can also be useful to take someone with you - particularly if you are experiencing problems with memory and anxiety.


Thank you Gambit62 for your advice. It took me forever but I finaly put a letter together to my GP and will be sending it today. Im very anxious about them thinking Im teaching them what to do. I can only wait and see now.


you always have the option of getting someone else to look at the letter to check that it reads as factual which is what you should be aiming for -

GPs are just generalists and that means that they should recognise that they don't know everything so the important thing is not to come across as saying 'you should know this and I shouldn't have to tell you!'. There is always the possibility that they won't have the self confidence to be comfortable with acknowledging that they can't possibly know everything but cross that bridge if and when you come to it. You have used a source that they can refer back to and should regard as authoritative.

Hope it gets the results you need.


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