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Heamatologist shocked with frequency of my weekly jabs

Hi, I have just come from seeing a consultant haematologist privately who was shocked to find that my GP has prescribed weekly B12 injections. He was even more concerned when I explained that I was injecting myself... he said I could cause an infection!

My GP has been very good at allowing me to trial more frequent injections but now I fear he will go back to monthly jabs once he gets the consultant report through.

Heamatologist has said that he will diagnose pernicious aneamina as all else has been ruled out. i explained to him that I have had for 2 years a continual pain under my left shoulder blade that is apparently due to narrowing in my facet joint in my neck. This nerve pain did not respond well tonerve meds , acupuncture and steroid injections but since my b12 went low the pain which was continual disappeared. I told him that a few days after my injection the pain comes back but then goes my the end of the week so I thought it was due to by nerve function improving with the B12 jab. Obviously I don't want the pain but saw it as a clear sign that the B12 was affecting my nerve function. He said it would only ever effect peripheral nerve function and that this cannot be the case.

He wants me to wean my self off the frequent injections!

Came out if the room and burst into tears i feel like I am being treated as a hyperchondriac.

Please help and if anyone knows someone who really is an expert in this area that I could see in the Surrey area?

Many thanks


11 Replies

Perhaps your haemotologist should read this Julie74 - sorry it's long I couldn't find the link

"Treatment with high dose vitamin B12 been shown to be safe for more than 50 years

Out of fear of overdosing vitamin B12, treatment is often reduced to below the frequency that is needed by the patient, or, even worse, treatment is stopped completely.

As a result, symptoms can reoccur again and again and even become irreversible.

It is very clear this fear of overdosing is based on a misunderstanding. For over 60 years high dose vitamin B12 treatment has been used without any signs of the danger of an overdose.

The Dutch National Health Counsel and the Regional Disciplinary Medical Board of Eindhoven have stated clearly that vitamin B12 is non-toxic.

Clinical research and the treatment for cyanide poisoning have shown that even extremely high doses of vitamin B12 and the serum values that go with it are harmless.

A decennia long history of safe treatment

In 1926 it was discovered that patients with pernicious anaemia could be saved from a certain death by eating a pound of raw liver a day. More than 20 years later the substance that was responsible for that was isolated from liver extract: vitamin B12 or cobalamin. Since then numerous patients have been treated with high dose vitamin B12 worldwide. Usually per injection and often lifelong, as a deficiency is mostly caused by an irreversible absorption disorder. In all that time harmful effects have never been shown from overdose. No single case has been found in medical literature in the past 60 years.

No maximum dose

The Dutch National Health Council therefore decided not to determine a safe upper intake level for vitamin B12. In their report from 2003 “Voedingsnormen: vitamine B6, foliumzuur en vitamine B12” the council joined expert commissions from the American Institute of Medicine and the Scientific Committee for Human Food from the European Union, who had already reported 3 years earlier that toxicity from high dose vitamin B12 poses no real danger.1

Of course, like with any medical treatment, side effects can occur. Acne, eczema and itching seldom occur and very rarely anaphylactic shock. Changing brands of vitamin B12, forms of B12 (cyanocobalamin vs hydroxocobalamin), or switching from injections to tablets can be a solution in those (rare) cases.

Misunderstandings about blood and reference values

Yet often physicians reduce injections or even stop treatment altogether out of fear of overdosing B12. The result is that many patients are left with recurring or lasting symptoms, which could be relieved by more frequent injections. After an injection the serum B12 value rises quickly, well above the upper reference value (on average 150-700 pmol/L), followed by a slow decrease. Apparently the underlying thought is that it is necessary to keep the value between the (upper and lower) reference values. However the blood level of serum B12 rises regardless of therapeutic effectiveness.2

A high serum B12 value does not mean that symptoms are treated sufficiently. This presumption can have damaging effects for patients with neurological symptoms, which can become irreversible with insufficient treatment.

Treatment based on symptoms instead of blood values

The recommended treatment in the Netherlands consists of a hydroxocobalamin injection of 1mg every two months, after an initial loading dose of 10 injections in 5 to 10 weeks.3

No reference is made to the serum value or a danger of overdosing, unlike for instance in case of a vitamin D or A deficiency. The lack of danger of an overdose is further underlined by the advice to treat patients with neurological involvement with two injections a week for up to two years, if necessary. This also emphasizes that symptoms and not blood values should be used as a guideline. If serum values were decisive, even patients with neurological involvement could suffice with the maintenance dose of one injection every two months after the initial loading dose.

Elevated serum B12 values in serious conditions

Maybe the concern for a possible overdose is caused by the knowledge that some life-threatening diseases can be accompanied by a strong increase in the B12 blood value, in some cases to even 30 times the upper reference value.4

In blood diseases like leukemia, polycythemia vera and hypereosinophylic syndrome, the cause is often an enhanced production of the transport protein haptocorrin, to which most of the circulating B12 in blood is bound.

In liver diseases such as acute hepatitis, live cirrhosis and liver cancer, elevated B12 values are often found because the liver is no longer capable of storing vitamin B12.

Elevated B12 values are always cause for further testing, but of course, to the contrary, it cannot be concluded that elevated levels after B12 injections leads to serious disease.

Scientific research

Scientific literature offers numerous examples from which it can be concluded that treatment with high dose B12 up to very high serum values is no cause for concern.

In the treatment of children with an inborn error in the production of transcobalamin II, the binding protein that transports B12 to the cells, serum values are kept at levels of 10 000 pg/ml (about 7 400 pmol/L) without any side-effects.5

Japanese research from 1994 into the effects of B12 therapy in patients with multiple sclerosis shows that a daily tablet with 60 mg methylcobalamin during six months is non-toxic. Half of the patients even started with two weeks of daily 5 mg B12 injections straight into the blood. 6

In the fifties, when chemotherapy wasn’t available yet, children with neuroblastoma (a tumour of the autonomous nervous-system) received 1 mg B12 injections every other day during 2 to 3 years in a London children’s hospital. From 1957 the dose was adjusted to 1 mg per 7 kilograms of body-weight. In the majority of patients the tumour disappeared wholly or partially and the chance of survival was considerably increased.7

In 1999 in Japan, kidney dialysis patients with polyneuropathy, received 0.5 mg methylcobalamin 3 times a week intravenously for 6 months. Because of lack of renal clearance, serum values rose to more than a hundredfold from 422 pmol/L on average to 54 000 pmol/L, with 67 000 pmol/L as highest value, without side-effects. 8

Also in Japan, in 2007, patients with the incurable neurodegenerative disease ALS (Lou Gehrig’s disease) received daily injections with 25 mg methylcobalamin for 4 weeks, followed by daily injections of 50 mg intravenously, followed by 50 mg a week. In the long term, treated patients survived for longer because of this, than did untreated patients.9

Megadoses B12 as lifesaving antidote

The safety of vitamin B12 treatment is further illustrated by the decennia long use of hydroxocobalamin as an antidote for cyanide poisoning, often caused by smoke inhalation. In the Netherlands ambulances, fire departments and emergency rooms have the Cyanokit at their disposal. In life threatening situations 5 mg hydroxocobalamin is given intravenously within 15 minutes, an amount that corresponds with 5 000 injections of 1 mg B12.10 Hydroxocobalamin reacts in the body with cyanide, and forms cyanocobalamin, which is excreted in urine.

The serum value of B12 can rise to an average of 560 000 000 pmol/L within 50 minutes.11

If necessary this treatment is repeated within several hours, making the total dose 10 grams. The side effects that occur, like reddening of the skin and urine and changes in heart rate and blood pressure are temporary and harmless. In short: 10 000 injections a day are still not enough for an overdose of vitamin B12.

Regional Disciplinary Medical Board: vitamin B12 cannot be overdosed

In 2009, the Regional Disciplinary Medical Board in Eindhoven stated very clearly that an overdose is not possible: “There can be no question of an overdose of hydroxocobalamin, as the excess is excreted in urine by the kidneys and therefore cannot accumulate in the body.12 The Medical Board ruled against a patient who claimed his deteriorating health was due to the continued treatment with B12 injections. The patient received monthly injections for 10 years. The physician was not rebuked because the patient was treated according to guidelines.


A vitamin B12 deficiency can cause many different symptoms, among which are serious neurological problems. The treatment with high dose B12 injections is not only completely safe but fortunately also very effective. With the right treatment patients can recover completely. Starting straight away with treatment is essential, as is the continuing treatment in order to give the body enough B12 to fully recover. Therefore it is essential that patients are no longer exposed to the real danger of irreversible symptoms because of the imaginary fear of overdosing.


1. Voedingsnormen: vitamine B6, foliumzuur en vitamine B12. (Nutritional standards: vitamin B6, folic acid, vitamin B12) Gezondheidsraad.Publicatienr. 2003/04, Gezondheidsraad, (Dutch National Health Counsel) Den Haag 2003:130-31

2. How I treat cobalamin (vitamin B12) deficiency. Carmel R. Blood 2008;112: 2214-21

3. College voor Zorgverzekeringen. Farmacotherapeutisch Kompas. CVZ, (pharmaceutical reference book) Amstelveen 2011

4. De betekenis van een te hoge cobalamineconcentratie in het bloed. (the significance of a high cobalaminconcentration in blood) Ermens AAM, Vlasveld LTh, Van Marion-Kievit JA, Lensen CJPA, Lindemans J. NTvG 2002;146:459-64

5. Inherited disorders of folate and cobalamin transport and metabolism. FentonWA, Rosenblatt DS. In: Stanbury JB ea. (eds). Online Metabolic & Molecular Bases of Inherited Disease, The McGraw-Hill Companies,

New York 2001:3897-933

6. Vitamin B12 metabolism and massive-dose methyl vitamin B12 therapy in Japanese patients with multiple sclerosis. Kira J, Tobimatsu S, Goto I.Intern Med 1994;33(2):82-86

7. Neuroblastoma: an evaluation of its natural history and the effects of therapy, with particular reference to treatment by massive doses of vitamin B12. Bodian M. Arch Dis Child 1963;38(202):606–19

8. Intravenous methylcobalamin treatment for uremic and diabetic neuropathy in chronic hemodialysis patients. Kuwabara S, Nakazawa R, Azuma N, Suzuki M, Miyajima K, Fukutake T, Hattori T. Intern Med 1999;38(6):472-75

9. Clinical trials of ultra-high-dose methylcobalamin in ALS. Izumi Y, Kaji R. Brain Nerve 2007;59(10):1141-47

10. European Medicines Agency (EMEA). Europees openbaar beoordelingsrapport (EPAR) Cyanokit,Londen 2007

11. Hydroxocobalamin as a cyanide antidote: safety, efficacy and pharmacokinetics in heavily smoking normal volunteers. Forsyth JC, Mueller PD, Becker ChE, Osterloh J, Benowitz NL, Rumack BH, Hall AH. Clin Toxicol 1993;31:277-94

12. Regionaal Tuchtcollege voor de Gezondheidszorg te Eindhoven. (Regional Disciplinary Medical Board Eindhoven verdict) Uitspraak van 15 april 2009 nr. 113b Juni 2011



Thank you so much Clive I will be printing all of this out for my GP.

1 like

Hi Julie74. I'm shocked that your heamatologist was shocked...more to the point, I'm appalled.

And his claim that B12 deficiency can only affect the function of peripheral nerves - well oh how we wish. Try telling that to someone who is suffering from sub-acute combined degeneration of the spinal cord (due to late diagnosis or undertreatment with B12).

His level of ignorance is truly frightening.

As for causing an infection when injecting - I'm going to guess that we all take very good care of hygiene and sterile technique when injecting ourselves - possibly much more so than some nurses who often fail the basic hand wash test (as per the two in my surgery).

Self injecting is not rocket science - unless, that is, you happen to be a condescending and unpleasant sounding haematologist. Strangely enough, anybody can learn to do it 💉💉

From reading your previous post it seems that the frequent regime was working for you and I see no reason why you should 'wean yourself off'. What does he think you are...an addict. Shameful.

Hopefully your GP will ignore him if he writes and suggests you reduce your injections, and let you carry on as you are. But, if the worst happens, take heart, you can buy supplies from Germany (not too expensive) and carry on getting the B12 for self-injection. We can advise suppliers if you go down this route.

The only good thing to come out of this is that you now have a PA diagnosis - which means that any GP you have in the further will not be able to simply withdraw treatment (whether they will prescribed enough for your particular needs is a different matter. Unfortunately.

I'm really sorry that he made you feel like a hypochondriac (good doctoring, that!). The fact that you left in tears is just dreadful...humiliating, demoralising...how dare he do that to you. It's very unfortunate (to put it mildly) that you have to pay him for the service he gave you. Not.

Please be reassured that you are not a hypochondriac - you have very real symptoms due to a very real condition - which he was magnaminous enough to to diagnose you with (note the little hint of sarcasm). But you know that. So ignore him and don't let him beat you. And oh how sad that we have to say such a thing about a person whose main role is supposed to be to care for you. And help you get well.

So, onwards, I say. Hope you are feeling a little better now and, as always, lots of people here to help if and when needed.

Take care...and a big hug 😀

P.s. Hope clivealive's wonderful cut and paste helps 👍


Thank you so much I'm feeling less emotional about it all now and will prepare to do battle. My husband is coming with me for support and as a witness to how much better I am since being on weekly jabs.

Many thanks


👍👍Really good idea, taking your husband.

Good luck and please let us know how you get on 😀


he said I could cause an infection!

Oh yes. That's the reason why they don't allow diabetics to inject themselves!



Hi Julie,

So sorry to hear you had a difficult time.I am not surprised at neurologists' comments about frequent injections having experienced ignorance from neurologists in the past.

I have also been made to feel a hypochondriac and was more or less told so to my face and yes I left my previous surgery/neuro appts crying on more than one occasion having been spoken to aggressively and even shouted at.

I was told once about someone who needed the equivalent of several b12 jabs a day to resolve their symptoms. There are also a few people who are fine on a one injection every 3 monthly regime. I seem to need huge amounts of B12 as symptoms return quickly. I think B12 requirements are very individual as we are all different.




You can always rely on this forum to provide support.

As Foggyme says at least you have a PA diagnosis for which there are recognised guidelines.

b-s-h.org.uk/guidelines/ Click on "Diagnosis of B12 and Folate Deficiency"

Also see BNF (British National formulary) Chapter 9 Section 1.2


For future appts as well as reading the guidelines above, I'd recommend looking at the summary fbirder compiled. See last link in third pinned post, also a link to summary on his profile page. Lots of useful quotes from mainly UK b12 documents that I have found helpful when dealing with medics who haven't done their homework on B12.


Thank you for your response and brilliant advice. This group keeps me sane , I think otherwise I would really start to think maybe it is just me. I am seriously thinking of going down the self medicating route just need to work out where and what to buy!

Many thanks


Thank you everyone for your responses and all the useful links. I have made another GP appointment to discuss this and will go armed with as much information as I can.

Many thanks



Hey Julie74 have you ever had your spleen checked. The is a link between b12 deficiency and your spleen. And spleen pain is in your left shoulder boss and down the left side.

1 like

Sorry I didn't see your reply! Thank you I will check this out although I have had MRI and they said it's coming from my neck. I think I had an ultra sound which ruled out spleen issues and I had full upper body MRI so think it would have picked that up but I will certainly look into this .

Many thanks



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