Pernicious Anaemia Society
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B12 injections

Hi there, I joined healthunlocked again a couple of days ago after a 2 year absent. I left as I had a mini breakdown caused by my ill health which includes scoliosis, sciatica,  spondylotis,  osteoarthritis and other problems. Also I suffered bullying from a lady that is no longer on healthunlocked. 

Anyhow, about three years ago I started suffering from leg cramps at night,  constant tiredness,  numbness down my right hand side of body. Then the leg cramps were happening during the day, when I was sitting, standing up and even walking. Early last year, after seeing so many doctors, I saw a new doctor who had started work at the surgery.  He asked if I had ever been tested for B12 which I hadn't, so I had the blood test. To my surprise it was 49 which was dangerously low so I had a course of 6 injections and now I have an injection every 3 months. 

I still  suffer from numbness down the right hand side of my body but it comes and goes. I started getting leg cramps but that's because I'm due my injection. 

I've been told that because I had this B12 definicity for so long beforehand that I have damaged my nerves?

My questions are have I damaged the nerves in my right leg.?

How exactly does B12 work in the body.? and what else can I do to improve it?

I'm a bit in the dark about B12 and what  it does .

9 Replies


I've assumed you are in the UK.

this quote caught my eye..

"it was 49 which was dangerously low so I had a course of 6 injections and now I have an injection every 3 months. "

If you have neurological symptoms, the standard UK treatment is loading injections every 2 days for as long as symptoms continue to get better then injections every 2 months. 6 loading injections followed by injections every 3 months is the standard UK treatment for B12 deficiency without neuro symptoms.

"numbness down my right hand side of body"

My understanding is that numbness is usually considered to be a neuro symptom. Do you have other neuro symptoms eg tingling. pins and needles etc. See links to Symptoms lists below.

pernicious-anaemia-society.... See Symptoms Checklist

Inadequate treatment of b12 deficiency can lead to permanent neuro damage. Some people experience an improvement of neuro symptoms after many years of illness if they get the right happened to me although in my case I had to self treat as I was unable to get treatment from NHS.

Uk treatment info

1) BNF (British national formulary) Chapter 9 Section 1.2

2) BCSH Cobalamin and Folate Guidelines

I gave a copy of this document which came out in 2014 to my GP, and would recommend reading the whole document.

3) link contains info similar to BNF in Management section

Have you read Martyn Hooper's latest book? It came out in Oct 2015.

What You Need to Know About Pernicious Anaemia and Vitamin B12 Deficiency

Other links

Link about writing to GP if unhappy with treatment, Point1. Neurological symptoms - suffering from under treatment.

PAS (Pernicious Anaemia Society)

Lifetime membership costs £20. The PAS can sometimes intervene on behalf of members.

pernicious-anaemia-society.... 01656 769 717


Hi Sleepybunny, thanks for your reply. I'm glad that I wrote my little paragraph as I've been in the dark about B12 since being diagnosed. I suffer terrible pins and needles mainly in my right arm and hand,  to get rid of them I massage my arm and hand and try to stretch my arm but it's difficult as I've arthritis in my hands.

I live in Wales and waiting to see a specialist  about  My back as I have double scoliosis and after having a MRI scan they have  found other problems with my nerves and vertebrates in my lumbar area. The strange thing is that they sent me for a MRI scan as I was waking up in the morning paralysed from the waist down.  So thinking about it, it could  all be connected. 

I've suffered from scoliosis  for 20+ years and it was only when I had a bout of pneumonia in Nov 2011 that my health took a nose dive. Since then I was diagnosed with Emphsema,   Bronchial (build up of mucous) B12, Overactive bladder and Osteoarthritis. The Emphsema is the worse as I used to be active but now I'm not, I try so only do what I can.

Sorry for waffling  but you seem to know what you are talking about, I've tried to find answers from the doctors but  they dnot seems to care.

Thanks again ☺


Hi Bentleyboo,

Welcome to our forum.



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I would ask to be referred to a neurologist, who can check out your nerves to see if the damage is consistent with B12 deficiency. I would also ask my doctor to increase the frequency of injections, but I wouldn't hold out too much hope of them agreeing.

If that fails you could try supplementing yourself. Sublingual tablets, mouth/nasal sprays and patches have all been tried with people reporting success with them.

Ultimately you could always consider self-injection.


You have obviously had symptoms of B12 deficiency that have been missed for quite some time.  Unfortunately that isn't uncommon.

I would definitely push for more frequent B12 on the grounds that you have neurological symptoms - and your loading doses should have been 3x a week until symptoms stopped improving.

B12 is used by a number of systems in the body so deficiency affects multiple systems - the bladder problems may be related to B12 - same for many of the other symptoms you mention.  Think sleepybunny has provided you with links to checklists where you will be able to get an idea of the full range of symptoms and start to put together what is relevant to you.  Unfortunately many GPS (and other medics) aren't aware of the full range of symptoms and some confuse it with anaemia - which is a symptom but not the cause.

A deficiency usually arises from an absorption problem - which could be

a) PA - autoimmune response that attacks the mechanisms in the ileum where most B12 is absorbed

b) low stomach acidity (symptoms often mistaken for high stomach acidity)

c) gastric surgery afffecting the ileum

d) a whole raft of drug interactions

B12 is only found in animal products so it is possible for a deficiency to be dietary if you have little or no meat/fish/eggs/dairy in your diet.

Normally the body is very efficent at storing and recycling B12 - store in liver and release in bile into the ileum for reabsorption  ... but if you have an absoprtion problem this won't work any more - so you will need injections for life.

Once you have started receiving treatment for a B12 deficiency further blood tests don't mean much UNLESS they come back with low results - indicating that your kidneys are quite efficient at removing the B12 from your blood - so you need more frequent top-ups.  The serum test says nothing about what is happening with the B12 getting from your blood to the cells where it is needed - which is why high results don't mean much.

B12 isn't toxic

There is a close working relationship between B12 and N9 (folate) - with both being required for a number of key processes - so it is important to make sure that your B9 levels are good, otherwise you may not be able to absorb and use B12 properly.

There are 4 different forms of B12 - cyanocobalamin, hydroxocobalamin, methylcobalamin and adenosylcobalamin.  The first two need to be processed into the last two which are the forms used at the cell level.  How you respond to each of the different forms varies a lot from person to person so if you try supplementing for yourself then it is worth trying different forms to see you respond.  Personaly I find hydroxo best for neuro-psychiatric, methyl for some neurological issues and adenosyl for bladder issues, but every one is different.

Supplementation generally involves doses of around 1000-10000mcg and generally you are looking at using a membrane outside the gut for absorption - eg in mouth, nose or the skin.


"I live in Wales "

It might be worth considering joining the PAS. Their head office is in Bridgend.

pernicious-anaemia-society.... address details on Home page.

There is also a South Wales PAS support group. Contact details in link below from News section. If you ring PAS they can probably give you more details.

 01656 769 717


I have read that one characteristic symptom of B12 deficiency is proprioception difficulties. I found it helpful to read about proprioception (awareness of body in space) and certainly feel I had some proprioception difficulties before I started to take B12.

Older HU posts about proprioception

Have you ever had a Romberg test?'s_test

I am not a medic just a patient who has struggled to get a diagnosis.

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Hi Sleepybunny, thank you for your reply, I will phone PAS on Monday and find out if they have a group in North Wales. I'm thankful  that  you know a lot about the condition as I've been in the dark since being diagnosed. I know you are not a medic but you are  a well informed  person, and I'm so glad you are as you have helped me and the many people on here with your knowledge about the condition.

What is a Romberg test? I've never heard  of it.

Gan 😊

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Bentleyboo, thinking about your bronchial symptoms, I wonder if you would consider removing dairy from your diet? I have had ruptured eardrums and moderate hearing loss caused by infections and since really limiting dairy I have not had one infection. My nutritional GP supports my idea that dairy was the problem. 

Also, many PA sufferers find a gluten free diet is most helpful in restoring the damaged stomach. I was diagnosed last year and since I am 62 (living in Australia ) there has been quite a lot of damage to the ileum. 

I have learnt how to self inject (my GP knows) because I found the 3 month wait was sheer torture. Now, my burning feet and tingling hands alert me to the need for an injection. I was losing words (scary dementia) and quite incapacitated but since achieving the correct levels of B12 I am really healthy. Currently in Venice, I am coping with all the vigorous exercise required and rarely lose words now. I have extra medication with me because exercise does use up B12 more quickly. 

In Australia, it is the 'Gold Standard' to have an endoscopy to check the state of the ileum and to achieve a thorough diagnosis. Not sure if your system would provide this but certainly worth an ask. 

The very best of luck in your recovery. You will need to be your own advocate - take lists of symptoms back to the doctor and try to get them onside. You have serious symptoms and hopefully, many of them will respond well to sufficient medication.

Good luck!



A Romberg test is when a patient is asked to stand straight with feet together and eyes closed. If the person becomes unsteady,sways or topples over this is a positive Romberg test.

I think most neurologists/doctors carrying out this test would make sure another person is on hand to catch someone if they fall. I also think it is not a good idea to attempt this at home due to the risk of falling and injury.

The problem for a lot of people with possible B12 deficiency is that neurologists sometimes don't do neuro tests with eyes closed. I saw several neurologists including a private neurologist, a few years ago and not one of them asked me to do neuro tests with my eyes closed. I was certainly aware of swaying or being off balance when my eyes were closed or when I walked at night or in the dark. Another question I was asked by someone who was knowledgeable about B12 deficiency was whether I could walk heel to toe with my eyes. I could manage it but felt very unsteady.

If I ever have neuro tests again I will request that I have test with eyes closed including the ones mentioned above.However my balance has improved since I started to self treat with B12.

The PAS might be able to tell you more about neuro tests that are helpful in establishing whether there are proprioception difficulties.

I had to become well informed and my own advocate after I realised that no-one else was going to help me find out what was wrong....I had some unpleasant experiences with medics. I spent time reading lots of old posts on HU and had a lot of support from other members. I read Sally Pacholok's book "Could It Be B12" and several of Martyn Hooper's books.

Gluten Free

Bethatthe beach mentions going gluten free. I had IBS for several years which disappeared when I cut out gluten, dairy and reduced sugar. Coeliac blood tests were negative but I found out later that it is possible to have Coeliac disease even if blood tests negative...see link.


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