Pernicious Anaemia Society
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Long term B12 maintenance


I'm struggling with my GP and B12... I was diagnosed as deficient about ten years ago and have been having quarterly jabs. I've also had lots of 'mystery illnesses' including some problems with my bowel/gynae (they can't decide which), mental health issues (depressed, but now on all the antidepressents and still can't get out of bed). I'm forgetful, weak as a kitten, clumsy and feel sort of fluey at times. I've had constantly bad sinuses (which were operated on) and now have constant sore throat/earache/sore tongue.

My last jab was two weeks late and the days leading up to it I just slept! I could barely lift my shoes to walk, my fingers were tingling, I could see stars, couldn't get enough air... It felt like the gravity had been turned up and the oxygen turned down!

I went for my jab and asked the nurse to check my levels as I was feeling some pretty extreme symptoms. She asked the doc and he said no as my previous serum level was 395. But this was six months ago and two days after a jab! Surely if three monthly jabs were enough I should have high levels, not borderline? Especially if I just had my jab? So I had my jab and the nurse made me an appointment to see the GP the next day to be retested as she agreed it sounded off. I spoke to the GP who said that 395 was fine, but they would need to test me before my jab to get an accurate level so I'd have to wait three months! I asked her how a level taken straight after a jab was taken as accurate, but one taken now, straight after a jab wouldn't be but she had no answer. I then suggested that, as my levels were questionable, I had symptoms, was already prescribed B12 jabs and it did no harm to have 'too much' that maybe another top up now would negate the need to feel like this for another three months if it worked, and if it didn't we could spend that three months trying to find the real problem. She got cross then!

So I'm confused about where my levels should be. It was my understanding that the first set of weekly jabs should get your levels up to and beyond 'good' and that the quarterly jab should keep this 'good' level topped up. In fact, as I had been so poorly when it was diagnosed (serum level of 11) my levels should be 'high' to help healing. I've also been led to believe that your levels would be 'high' after a jab, and then be 'ok' by the time of the next one - sort of like recharging a battery when it gets to half power rather than letting it drain completely. So if just after a jab my level was 'just about ok' if you take into account a margin for error, then it must be at 'not ok/low' by the time my next jab is due?

I feel I need a top up, more regular jabs (monthly?) and a proper review in six months. I feel utterly dreadful! Any ideas of what to say or why my levels might show borderline?

7 Replies

Your levels are meaningless. The latest guidelines from the BCSH - - says in the summary -

"The clinical picture is the most important factor in assessing the significance of

test results assessing cobalamin status since there is no ‘gold standard’ test to

define deficiency."


"In the presence of discordance between the test result and strong clinical

features of deficiency, treatment should not be delayed to avoid neurological


In other words - "Doctors should treat the symptoms, not the numbers"

It also recommends -

"Treatment of cobalamin deficiency is recommended in line with the British

National Formulary."

The BNF says that people with neurological symptoms (tingling finger/toes, depression, brain fog, etc.) should have injections every two months.

However, it can be difficult to get some doctors to agree (they obviously know better than the British Committee for Standards in Haematology who are only a bunch of the top experts in the land). Many of us have taken the route of self-medication.

Some do self-injection, but many find that alternative, not so spiky, means of supplementation help. There are sub-lingual sprays and lozenges, nasal sprays and skin patches. All have their fans. I would recommend trying one and see how you get on with it. If it works - great, if it doesn't then try another form. Or take it more frequently than the recommendations. It's not possible to overdose on B12, so feel free to experiment.

The only caveat about self-medication is that your blood levels will skyrocket and become even more meaningless. Your doctor may think he's a miracle-worker and refuse all further treatment until your levels get back to 'normal'. So do inform him beforehand.


I'm sorry you're having such a frustrating time with your doctor. I'm glad you pointed out the discrepancy of thought that your previous reading after a jab could be compared to a reading right before one. (The only time a comparison like that is useful is if you have your level tested after a jab and then again right before the next one to determine what your rate of loss looks like. Even then the result just gives you an idea of how quickly you use up an injection.) It's actually a little insane that your doctor thinks a level of 395 after a jab is normal. I can only speak from my own experience, but my level after a jab is over 1000.

It would be a miserable experience, but if you did hold out for three months and get your blood drawn before your next jab, it would most likely come back as borderline or low. But, probably, the only benefit of doing it would be the I-told-you-so moment you'd have. If you're lucky, it might prompt your doctor to increase the injection frequency. If you're unlucky, it will just cause your doctor to dig in and refuse to help.

One thing that might be helpful is a complete blood count. Seeing stars and feeling short of breath are likely to be signs of anemia. If you're blood still shows that you are anemic, that would be additional ammunition in the fight for increased frequency of injections. Have you requested copies of your previous labwork? It is best to get the actual numbers (including the lab's reference ranges) rather than relying on a doctor saying all is normal.

I agree with fbirder. At this point it is your symptoms that matter the most. Those need to be taken seriously and treated.


"Surely if three monthly jabs"

The fact that you are receiving three monthly jabs suggest you are on the standard NHS treatment for B12 deficiency without neurological symptoms. You mention tingling which is usually considered to be a neurological symptom. Treatment for B12 deficiency with neuro symptoms is more intensive.

How many loading injections did you originally have? Following link has info similar to BNF. Scroll down to Management section.

Do you have other neuro symptoms?

There is also a symptoms list in PAS library section on website.


"I was diagnosed as deficient about ten years ago"

Were you diagnosed with PA (Pernicious Anaemia)? Did you have an IFA (Intrinsic Factor Antibody) test?

The PAS (Pernicious anameia society are helpful to talk to. If you leave a messgae they will get back to you.


01656 769467

Other useful websites/articles/books

"Could It Be B12" by Sally Pacholok

"What You Should Know About Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Your local CCG (Clinical Commisioning group) assuming you are in England should be able to tell you if your area is following BCSH Cobalamin guidelines. Not sure of equivalent organisation in Wales. Scotland , NI.

It can be useful to find out the local NHS guidelines for B12 deficiency management. Some local guidelines have not been updated since BCSH Cobalamin document came out in 2014.

A google search, search on local NHS website or FOI (Freedom of Information) request on local NHS website should locate them

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Your neurological symptoms should be treated with injections according to the BNF in the BCSH guidelines to avoid permanent damage.

"The BNF advises that patients presenting with neurological symptoms should receive 1000 ug i.m. on alternate days until there is no further improvement".

The above BMJ research document is supported by many research papers and has a useful summary if GP won't read the whole document.

It also tells GP (bottom of page 4 under, "How is response to treatment assessed") :

"Cobalamin and transcobalamin levels are not helpful because they increase with vitamin B12 influx regardless of the effectiveness of treatment and retesting is not usually required".

In other words, once b12 treatment is started, the serum blood test results are not reflective of how effective the treatment - it is the clinical condition of the patient that matters....

I hope you are able to get more frequent injections and start to feel better soon MM.

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PS. The above is what should happen but, in reality, many GPs refuse to follow these guidelines. My relative with severe symptoms similar to yours is on monthly injections but treatment was left too long, was never frequent or aggressive enough early on and the family have now resorted to buying B12 for injection.


Hydroxycobalamin is an inactive form and you need to be able to convert it . If you can`t you will need the active form , methylcobalamin ,which is not available on the NHS . Google it and you will be able to source it yourself . Many pharma drugs lower b12 levels including anti depressants . I think you will find methylcobalamin much more helpful .


I've googled it and cannot find anywhere that can supply it except several US companies that can give 10,000ug in exchange for $150 and a (US) doctor's prescription.

Besides, most people have no problems converting hydroxocobalamin to methylcobalamin (otherwise their injections wouldn't work).


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