B12 deficiency symptoms, has anyone e... - Pernicious Anaemi...

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B12 deficiency symptoms, has anyone else experienced this?

Hi I've been getting b12 injections since October of last year and feel like things are getting worse instead of better. I've had countless blood and ecg tests and the latest have all come back fine. Now not sure where things go from here. Just wondering if all of these symptoms are typical of b12 deficiency and have others experienced the same thing.

Symptoms include: light headedness/dizziness, pain on the left side of the body (specifically arm, back, shoulder and neck), memory problems, awful fatigue, balance problems, short of breath, heart palpitations and just a general feeling of not being well.

19 Replies


"been getting b12 injections since October"

Sorry to hear you feel things are getting worse.

How often are you getting your B12 injections?

Are you in UK?

I'm asking because patterns of B12 treatment vary from country to country.

B12 websites


B12 Deficiency Info


Pernicious Anaemia Society



B12 Awareness





Hi I'm in the UK and I get an injection every 3 months. Thank you for the reply!


Hi again,

Symptoms of B12 Deficiency



Risk Factors for PA and B12 Deficiency




Unhappy with Treatment (UK info)?

Letters to GPs about B12 deficiency


CAB NHS Complaints


HDA patient care trust

UK charity that offers free second opinions on medical diagnoses and medical treatment.


UK B12 documents

Strongly recommend reading all of these if in UK.

BSH Cobalamin and Folate Guidelines


Flowchart from BSH Cobalamin and Folate Guidelines


BMJ B12 article






You mention 3 monthly jabs. BNF guidelines changed recently to say B12 jabs every 2 or 3 months.


How many loading jabs id you get at start of treatment?

In UK if no neuro symptoms ...

6 loading jabs over 2 weeks followed by a jab every 2 or 3 months.

If neuro symptoms present...

a loading jab every other day for as long as symptoms continue to get better then a jab every 2 months.

B12 books I found useful

"What You Need to Know About Pernicious Anaemia and B12 Deficiency" by Martyn Hooper

Martyn Hooper is the chair of PAS (Pernicious Anaemia Society). Book does not mention recent BNF change.

"Living with Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Has several case studies.

"Could it Be B12?: An Epidemic of Misdiagnoses" by Sally Pacholok and JJ. Stuart (USA authors)

Very comprehensive with lots of case studies. There is also a paediatric version of this book "Could It Be B12? Paediatric Edition: What Every Parent Needs to Know".

PAS (Pernicious Anaemia Society)

Based in Wales, UK.


PAS tel no +44 (0)1656 769717 answerphone

PAS support groups in UK




I have written much longer replies on other threads, may be worth you searching for them.

More b12 info in pinned posts on forum.


I got 6 loading jabs over 2 weeks and then every 3 months thereafter. Thank you so much for all the info, I've felt like I've slowly been losing my mind with all of this. Finding this forum has been such a help.


Hi & yes to everything you have mentioned, I felt like a hypocondriac!!

For some, (most) people with PA the laws in this country, now every 2-3 monthly injections are not enough.

Loads of people have had to take their health into their own hands & self inject to keep symptoms at bay.

Good luck

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Thank you for the reply! I have just been told I'm just anxious or a hypochondriac by my current doctor. Just got a change of doctor, so fingers crossed things will improve. I think self injection is going to be my only option at this point.

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Anxiety is a b12 symptom, and who wouldn’t be anxious when their body does weird stuff?



"got 6 loading jabs over 2 weeks and then every 3 months"

This is standard UK treatment for B12 deficiency without neuro symptoms.

If you have neuro symptoms or had neuro symptoms then my understanding is that in UK, you should be on...

a B12 loading jab every other day for as long as symptoms continue to get better then a jab every 2 months.

I am not medically trained.

Is your GP fully aware of the potential consequences of under treatment of B12 deficiency?

Neurological Consequences of B12 Deficiency

PAS news item


PAS article about SACD, sub acute combined degeneration of the spinal cord, access to PAS members only.

pernicious-anaemia-society.... See Page 2 of articles.

Blog post from Martyn Hooper's blog, mentions SACD


Letters to doctors about under treatment of B12 deficiency with neuro symptoms


Have you been tested for PA?

In UK, this would be an Intrinsic factor Antibody test. IFA test is not always reliable and it is still possible to have PA even if IFA results are negative (Antibody Negative PA).

Some countries also use a parietal cell antibody (PCA) test but this is not recommended in UK as a diagnostic test for PA.

Blog post about how PAS can support those seeking PA diagnosis


Tested for Coeliac disease?

NICE guidelines Coeliac Disease (2015 version)


Coeliac Blood Tests


For H Pylori infection?


Have you considered joining and talking to PAS?


Or writing a brief, polite letter to GP expressing concerns?

A letter could contain symptoms, test results, relevant personal and family medical history, extracts from relevant articles and guidelines etc.

UK B12 Blogs

Martyn Hooper's blog about PA


B12 Deficiency Info blog


"feel like things are getting worse instead of better"

Has GP checked your potassium levels? Some people experience a drop in potassium levels ( hypokalaemia) when they start B12 treatment..see side effects section in next link.



Welcome to the club! I was diagnosed over three years ago and, although my symptoms have improved and changed I am still far from well. This seems to be the default for everyone with b12 deficiency/PA.

However, reading the blogs on here one realises just how worse off the majority are compared with oneself. And the humbling fact that they give up their time, though very ill in many cases, to help us all.

If there is an upside to any illness, it is the discovery that there are such kind and caring people in the world.

Good luck, it’s a long journey!


Thank you for the reply. The discovery of this blog has done wonders for my sanity. I've literally felt like I've been losing my mind for the past year and a half and felt so alone. All the members here are wonderfully supportive! May your health continue to improve:)

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you are not losing your mind....it is the illness that is B12 deficiency....I was in the very same boat as you and it took nearlyy five months of every day or every other day injections for any real improvement.....you need much more regular injections. healing hugs. J


So many great experiences being shared for you! I have the complication of a couple of different autoimmune conditions which cause a constant battle of what necessary component is going to “sit out” today? This is certainly a battle you do not want to fight a lifetime of without a dedicated, persistent and caring doctor at your side. For anyone new to this experience, if you are in a country where you can choose who is in charge of your medical care, and change doctors at will, never be afraid to find a new GP if the one you have does not support you and care about getting to the root of the cause(s) of your issues so that you can feel the best you possible. Your life can literally be at stake. No time to worry about hurting someone’s feelings or pride because you changed doctors. In my case, constant regulation of so many things in my body/blood is necessary to the point I’m not sure I would be here still if I didn’t have the doctor I do now. Many have discussed how important having all of your nutrients in sufficient supply and in balance is. It can be eye opening how much one thing that seems so inconspicuous can be to us. After getting over my biggest hurdles with B12, I had my symptoms return like an out of control train and felt devastated. My doctor found it was Vitamin D that had completely dropped and within days of beginning RT for it, I was better. Keep being your own biggest advocate and the right doctor for you will eventually find you!!


I know what you mean, it's a constant worry as to what's going to happen today. After a year and a half of this, I'm just so fed up. I've got an appointment with a different doctor, hopefully they'll listen and not just say I'm anxious or a hypochondriac. I'm 23 years old and should not have to feel like this. Thank you so much for your reply, it makes me feel I'm not alone and things will get better. Glad to hear things are better for you :)


Mine has been a lifelong journey as well. I started seeking help for my symptoms in general when I was 27 (I’m 46 now). I will keep your struggle in my heart, that it will be a much shorter one than mine has been. This is not meant to discourage you, but rather to let you know it is worth it to keep trying and change doctors until it feels right. In the year before I found my amazing doctor, I saw 20, literally twenty, new doctors. I left the one I had for years prior to that after her careless HIPPA violation led to me finding out how she really felt about me when she told another patient which she did not realize knew me WELL and immediately called me. That was the last time I gave the idea of switching doctors a second thought. If they aren’t helping you or visibly making the effort right away, there is a reason and whatever it is, it probably isn’t a good one and most definitely isn’t helping you. Any doctor who would take your issues as being a hypochondriac without taking the time to get to know you or learn about your medical history from you personally is not worth your time or resources. We all have days we break, but it sounds like you have learned to take it in stride and try to look at each new day as a new adventure in “What’s next?.... BRING IT ON!!” It is easy to feel alone at times, but know you absolutely are not! This group makes the world a smaller place, where we don’t have to feel alone even when you’re in the medical world of strange and unusual diagnoses. On the days you break you can always come here for the support you need to get through it. 💙 (PS I found this made a positive difference with my interactions with doctors. I let them know that I have experienced anxiety and I have experienced depression. I know what both of those feel like. Though similar in some ways, depression and/or anxiety are NOT the feelings I experience with this. It is very different. It feels like it comes from a different place. If you think that too, maybe this can help you verbalize it to your docs in a way they will listen.)


"Any doctor who would take your issues as being a hypochondriac without taking the time to get to know you or learn about your medical history from you personally is not worth your time or resources"

ThePATexan , another quote I totally agree with....I was diagnosed with hypochondria, told by specialists my symptoms were purely psychosomatic, that it was just depression etc despite suffering typical symptoms of B12 deficiency.

I stayed with a GP practice where I was not treated kindly, for far too long because it was easiest one to get to.

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The most tragic part is this is the case for most people who suffer conditions you can’t “see”. It really disgusts you when it’s a doctor who can’t “see” it. You want to shake them and say “It’s the PRACTICE of medicine! Do some practicing and run some diagnostic tests!” In my case, I had (key word is “had”) a Hematology Oncologist as my PC. She HAD run the right tests and had the proof of my condition years before I was severely symptomatic. She was just so convinced it was all in my head that she never even looked. That is why I tell anyone who has an issue with a doctor not to feel bad about dropping them and going some place else if it is at all an option. We don’t have time for doubters!


Hi ThePATexan

"never be afraid to find a new GP if the one you have does not support you and care about getting to the root of .... issues ...No time to worry about hurting someone’s feelings or pride because you changed doctors"

Couldn't agree more with what you said.


Hello jk003. In short, all of your symptoms could be B12 related. I had all of them myself until I started weekly self injections. Even with this frequency I still get some symptoms between jags. Like you I had chest pains - in my left side - and had several ECG tests ( which found nothing). My chest pain disappeared about 2 weeks after starting B12 supplements. I also had low magnesium and have just finished a 3 month course of supplements for this. Generally I feel much better than a year ago. I suspect that in your case you need a much greater frequency of B12 injections. I would also consider magnesium supplements. It also wouldn't do any harm to have you Vit D levels checked. Good luck to you!


Thank you for the reply. I have another appointment next week with a different doctor to try and get someone to listen. I'll mention the vit D to the doctor and see if they're willing to check it. Glad to hear you've found a treatment schedule that works for you. Keep well :)


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