Burning through B12: does anybody think... - Pernicious Anaemi...

Pernicious Anaemia Society

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Burning through B12


does anybody think it's weird that you'd have to inject so much B12 for so long just to feel normal? I mean if your stomach isn't able to absorb it that's fine. Or maybe you don't get it in your diet. But once you start injecting your liver should be storing it right? And after you saturate your liver you should be good for a while. Like months. So my question is... Is the body burning through B12 super fast because it's combating some other problem? Inflammation? Is the body unable to store all this injected B12?

63 Replies

There has been very little research done on Pernicious Anaemia, so your question can’t be answered yet P.A.S is trying to redress this problem ,which means expensive research has to be done . For the moment we just have to accept that the required regularity of injections needed by P.A. patients , to keep the symptoms of the condition at bay , varies enormously , from once or even twice a day, up to once in 3 months . . .... People without Pernicious Anaemia who eat animal products , do not have fish tapeworm, do not take B12 inhibiting medications, do not have certain diseases , do not use nitrous oxide , can store b12 in their liver for years .

The B12 stored in the liver is attached to haptocorrin (HC). The HC-B12 is unusable (it is 'inactive B12' as opposed to 'Active' B12 which is bound to transcobalamin). The HC-B12 is slowly excreted in the bile which empties into the duodenum.

At that point enzymes from the pancreas separate the HC from the B12, and the free B12 can now bind to Intrinsic Factor (made in the stomach). The IF-B12 does through the small intestine to the ileum, where the IF is absorbed, taking the B12 with it. The IF is then removed and the B12 enters the bloodstream. That is how B12 gets from the liver stores into the blood.

At least, that's the way it works in normal people.

But if you have PA then you don't make IF in the stomach, so the free B12 cannot bind to it and it cannot be absorbed in the ileum. The B12 just carries on through the gut.

So the B12 in the liver in inaccessible if you have PA.

wedgewood in reply to fbirder

Thanks for that . My GP was ignorant of that unfortunately. How come you know and GPs don’t ? Another reason why P.A. patients get short shrift from GPs . I had a diagnosis of P.A. ( positive I.F.A. test ) after my 5 injection loading dose , I was told I had enough B12 to last me for years , but to be generous I could have an injection once every 3 months , which I shouldn’t really need .

fbirder in reply to wedgewood

I know because I've been reading about B12 for five years.

GPs don't know because their study of B12 is limited to one wednesday afternoon, when they cover PA at the same time as other vitamin deficiencies with much cooler names.

researcher21 in reply to fbirder

Please can you advise me on where to buy B12 injections online. My level is 300 and GP says is normal!

Try German pharmacies.

Hidden in reply to fbirder

ah, i didn't realize that even liver stored b12 requires proper GI function. that at least makes sense. so when you are injecting you can only affect blood levels. anything stored in the liver has the same IF issues. bummer dude.

Mrsannabbott in reply to fbirder

Many many thanks for that clear explanation.I will keep it to present to the next nurse/doctor who tells me I have enough B12 in my liver to keep me going for a year.Can I just ask if repeated doses( 6) of various antibiotics for a persistent UTI would deplete B12. I inject 6wkly but am feeling all the usual symptoms of PA. back with a vengeance.I would be grateful for your opinion.

fbirder in reply to Mrsannabbott

I believe that some antibiotics can affect the absorption of B12, but that would be irrelevant if you're having injections. I've not heard of them reducing the amount of available B12 once it's in the body.

Mrsannabbott in reply to fbirder

Thank you.So will plod on.

I havent a diagnosis of PA. I need regular injections

For some reason even if stored in the liver my body is unable to access it or uterlises it??

I was told the same.

After loading doses I would need 3 monthly top ups and I'd be sorted.

My diet included everything.

My question was why did it deplete in the first place as on the same diet that has kept me well for 57 years ??

So if its broken it's broken.

We do need answers .

wedgewood in reply to Nackapan

It sounds as though you developed Pernicious Anaemia . You haven’t got a diagnosis , but that doesn’t mean you don’t have it . You know that about 50% of P.A. patients get a negative intrinsic factor antibody test , so don’t get a formal diagnosis .You were fortunate to have a doctor who had some knowledge .

Nackapan in reply to wedgewood

My doctor had no knowledge. She still says its dietary!!

She follows the neurologists treatment plan thank goodness

It can be an absorbtion problem on it's own or antybody negative PA

Cant remember term .

I've never had an IFA test. I tested negative for partial cell antibodies.

Roll on more research.

Thank goodness for b12 injections

I don't think it has to be PA. I'm pretty sure I can get B12 from my diet, however due to long term vegetarianism and repeated use of fluoroquinolone antibiotics (which are known to strip out B12) I became severely deficient for a long time without diagnosis. My system got damaged. I now take Hydroxocobalamin injections every four days. The amount I can get through gut absorption - via diet or supplements - is just not enough.

People with PA will need regular injections as they cannot get it through their diet and will not be able to make use of any storage as the recycling of B12 through the liver and gut will not happen.

People with a certain level of B12 deficiency damage (whether with PA or not) seem to have to take very regular injections and be swimming in B12 to avoid the worst of deficiency symptoms. We don't know why.*

* [I wonder whether it is because the system of getting it into the cells with transcobalamins has broken down in some way? We are only able to get it into our cells by osmosis**, so we need to keep our blood B12 levels high by regular injections.]

**Correction: I don't mean osmosis, I mean simple diffusion. It's been a long time since I studied biology at school and am getting my words mixed up!

Yrs I think you are right. Once on injections and the process also changes. I'm on every 6th day injections. After 2 years of only evef getting to 3 weekly on a few occasions on Gp instruction trying oral tablets as well. ! 2weekly for a year which I'm prescribed. Then lockdown so bought some. In hindsight

For me it was the menopause that made my absorbtion less efficient.

Obviously went down gradually until I crashed quite literally at a level of 106pg/l first ever b12 level taken.

Unbelievable really in hindsight.

Like you say the system is broken in some way.

An explanation would be good some day.

Meanwhile thank goodness for b12 injections with no worries of overdosing on trial and error.

I will look up osmosis


Good reply thanks

Seem to go round in circles hoping for improvements

Yeah, thank goodness for B12 injections and thank goodness it's one thing that can't be overdone.

I think osmosis is the wrong word! Has been a long time since I did biology at school. I am just meaning that because there is a high concentration of B12 outside the cell, some of it will end up going into the cell just by random movement. :-) I think it's called diffusion, not osmosis!

olicana1949 in reply to Nackapan

Assuming you are in the UK, how did you steer the GP into giving you twice weekly injections when I read GP's are reluctant to go more frequent than once every two months. I'm about to tackle my GP as my first 3 month booster has had no effect on symptoms.

Nackapan in reply to olicana1949

I had the loading doses. 6 over 2 weeks . I was then supposed to wait 3 months I was bedbound and getting more symptoms. Taking sub lingual and b12 tablets.

I found this forum.

I'd had a brain mri and ct scan.

I rang the surgery . I booked a b12 injection 5 weeks after loading.

When I got there it was refused.

I just sat. Didnt leave.

Waited for practice manager.

I was called. The only person I saw was a Gp so I went in.

It became apparent shed actually called in her patient. The call for me was from behind??

As saw I could hardly walk and was shaking violently

She didnt turf me out.

I asked her to read the bnf guidelines

I asked her to read the letter from neurologist.

She did.

Loading b12 every other day restarted .

I then went to weekly then 2 weekly and have been on that regime for 18m . Ever time challenged I fight .

I did try going 2 weekly taking prescribed 50mcg b12 tablets 3 times a day . I increased this ti 1000mcg a day. A couple of 3 week stretches but soon got more ill

I'm actually prescribed 2 weekly b12 injections.

I bought some and have it every 6th day at present.

Btw I'm still nowhere near my former self.

My Gp knows very very little. She says she is learning from me .

Not great.

I've resisted many antidepressants pushed my way

Have trialled amitriptyline and hrt in a bid to lessen headaches /migraine es / vestibular migraines.

Only on each and not at the same time for 3 weeks. Just made me worse.

Then covid hit the world.

Another fight to inject at home to save nurses time and my arms as very very sore.

It's been soul destroying pushing for everything.

No understanding of symptoms

Being sent down the mental health route

Being told to pace then being told to push through.

Anyone that states I'm lucky to have this treatment is wrong.

Anyone that says I'm lucky to have an understanding gp is wrong.

I see the best of 7

After working through them.

I've lost trust

I've lost confidence in their judgements

I've got that prescription at present as my very low b12 is the only thing that's been diagnosed.

I point this out if any opposition.

It's quite frankly exhausting.

At times dont even know anymore what to push for.

With less self will I would be on many drugs and be a very 'quiet ,'patient with alot of my symptoms put down to side effects of the drugs.

I will never forget refusing to leave the surgery. Never before have I been pushed to behave in a passive aggressive manner.

Never been rude just insistent.


I am in the UK

Yes I am very worried about the lack of knowledge with most Gps.

Just use all the facts and guidelines issued by PAS and bnf and haematologist experts.

Unless they can offer another diagnosis with another treatment it is their duty to treat us.

Pastie121 in reply to Nackapan

Hi nackapan just reading your post. I see you’ve refused the antidepressants, I done exactly the same because I believed I wasn’t depressed and that my anxiety came from whatever was happening in my body. After seeing rhumotologist she advised to take sertrilene supposed to help with nerve pain it was the I decided to start 2 x b12 tablet everyday. Previous to that I’d had a nerve root block injection. The combination of the three seems to have done trick for me. Touch wood.! I’ve had an mri on my ear after having vertigo for a month last April,and ear is still not right. They’ve requested another mri which I’m having Sunday night at 6.15! My point is why don’t you give the antidepressants a go. I’ve not felt better in a few year. Just another point before I had my hip replacement 5 year ago. I came off hrt which I had been on for 10 year always said I never felt the same after I came off it. Xx

Nackapan in reply to Pastie121

Yes it was sertraline and duloxatine amongst other offered. I was put off by the trail of amitriptyline. I had a bad experience. Also dreadful coming off it . I seen very sensitive to things .

I'm glad its helped you

Pastie121 in reply to Nackapan

Aw sorry to hear that it was just a thought xx stay safe x

Hidden in reply to Pastie121

the problem with antidepressants and what is not discussed much... you often do worse after you get off them and they are addictive. i have mixed feelings about my time on wellbutrin. on the one hand it convinced me i have major depression. it showed me what it's like to be a normal person. but after a year it started to poop out. i was started on 300mg which is high. my doctor assured me it wasn't addictive. yet it took me 3 attempts to get off it. each lasting about 3 months. in the first 2 attempts i went back to it because frankly i would do anything to stop feeling so terrible.

now that i am off and have been for maybe 3 years i've had the worst depression and fatigue of my life.

i think people's instincts are right when it comes to antidepressants. it's not a place you want to go to lightly. do consider carefully. you may never be able to get off them side effects be damned.

Nackapan in reply to Hidden

Yes I agree. A friend has had great benefits from sertraline Been on it years.

Decided she was in a better place and wanted to get off it.

She had depression.

Took her 4 attempts over a year.

Shes having to adapt and now after 6 mo ths feels better off it .

Long haul though.

I know I'm not depressed .

Down at times which is normal with a chronic condition giving daily pain and problems.

If an okayish day I'm a different person.

Some of these drugs are safe for life and it becomes the new you.

They are much safer but even although told not addictive I believe they are .

I was only in 10mg if amitriptyline fir 3 weeks. I was told baby doses no problems stopping if it doesnt help.

I was so drugged . When I was due to take it my brain would go into overdrive until drug recieved

It irritated my whole system. It was taken as advised by 3 neurologists and 2 gps. To prevent migraines and calm everything down. I got relief for 2 days as so drugged. Then headaches broke through on top. Hell.

My daughter had the same doses for 3 months and coped fine on it and got much relief from pain..

I've since read its not good for a vestibular disturbance and described what happened to me. That was reassuring.

The neurologist that gave the last push wanted me taken uk to 50 mg!!

Fortunately my Gp saw how ill I was on it and said not ti persevere and stop. She said cold turkey but I tapered it was very hard to get off. Took me a month to get back to where i started.

Everyone reacts differently. I know drugs help us. Its finding the one that suits.ive been offered about 9 now but not convinced and quite frankly scared by past experiences .you need into understand the problem first Gps work on trial and error some can tolerate this. I wish a drug made sense to me to try as do need relief. Has to be the right one!!

Still waiting for specialist appointment.Neuro Opthalmologist


Pastie121 in reply to Nackapan

Yeah I was on the amptriptolene for a bit but didn’t agree with me either x

LolajaneB in reply to Nackapan

I wish I had your fight. My body has just about given up now and Im losing the battle. Ive had PA since I was very young so basically all of my adult life of over 35yrs. Ive never had a doctor who knew about PA. I moved home not too long ago and the GP ran a blood test on me last year after my B12 jab. She said my B12 levels were great and I would no longer receive B12 injections as I didn't need them. I tried exiling my symptoms but she just said that they were not down to low B12 and that was it. I ended up so poorly I phoned the surgery begging for another jab. they relented and let me have one but Im still not recovered to what I was and don't think I ever will be now.

Nackapan in reply to LolajaneB

Give yourself time and regular injections . If you too poorly to fight with the gp at present i can understand that.

If a PAS member get their help with writing to Gp

Or look through posts. Bnf guide


Easier than face to face

As you have a PA diagnosis or b12 deficiency they are being negligent.

You need injections for life.

Whilst this being sorted . Which it will be perhaps self inject si you can get back on track

This is your health

Nackapan in reply to LolajaneB

I've made a new post about letter writing to gp when denied regular treatment. You should get more help that way

We shouldnt have to fight I agree.

You will find the energy to deal with this.

I wish you well.

T c

Thank you for asking this question and thank you all for your insight. I often wondered where all my b12 goes. Why, even with injections, my numbers aren’t as high as some and why numbers didn’t matter. So I just want to make sure I understand this correctly. Even with injections, you still have to be able to access the stored b12 in the liver and with P.A., this isn’t possible. Am I correctly understanding this? I always thought the IF was needed long before it ever made it to the liver.

Google "the enterohepatic circulation of B12". There's a pdf on the B12 deficiency info website about this. Is pretty complex, but if you are interested in the process and have enough of a scientific background to understand what is being said, you'll hopefully find the answer to your question! :-)

I will definitely look that up. Thank you🙂

JanD236 in reply to Plucky11966

Plucky11966, if you’re having injections you do not need to access stores in your liver. The injections get around the problem of not being able to access these stores (and indeed the problem of being unable to access B12 from food).

When everything is working properly, IF is needed twice. The first time to bind to B12 in food that’s just been eaten. The second time to bind to B12 that has been released from stores in the liver.

Nackapan in reply to Plucky11966

When injected it's used from in the blood directly.

Can I please ask what supplements you are all using as well as b12 injections. I self inject every other day but I'm so confused about the extra vitamins and how much folic acid I should be taking. Any help greatly appreciated

fbirder in reply to Clara5672

Injecting B12 does not increase your bodies requirements for folic acid, or anything else. Just as having an oil leak in your car doesn't mean that you need more oil, brake fluid, antifreeze, or windscreen washer fluid.

If you have a B12 deficiency caused by Pernicious Anaemia then you will have low levels of stomach acid. That can inhibit the absorption of Vitamin D, folate, and iron. That is why some people benefit from taking those as supplements. But you should only supplement iron after discussing it with your doctor.

The NHS recommends that everybody takes 10 mcg of Vitamin D each day during autumn and winter (and during lockdown when we're indoors more often). They also recommend that all women of childbearing potential take 400 mcg of folic acid a day - so that amount should be safe for anybody.

Clara5672 in reply to fbirder

Thank you for your reply. I have been following a "Facebook " group and since taking the levels of supplements they suggest, I have now got the most horrific itchy skin. I did have concerns about daily doses of 5mg folic acid

fbirder in reply to Clara5672

Quit that Facebook group now. They post dangerous advice and ban anybody who dares question their ideology.

Just try asking them who says you need 5 mg of folic acid a day.

They will reply "The files". ('The Files are their holy work).

Ask them exactly where in the file.

They will reply "Look for yourself"

Say "I've looked"

They will reply "It's in Sally Pachalok's book.

Ask "What page? Because I've checked every page where 'folic acid' and 'folate' and 'methylfolate' are listed in the index."

They will ban you from the group.

That's what happened to me.

Clara5672 in reply to fbirder

I was told that if I inject every other day I must take 5mg of folic acid or it's a waste of b12 as I'll just pass it when I go toilet. I'm so confused by all the contradictions on what supplements I should take and I feel I am doing my body serious damage. Thank you for your reply

In addition to previous answers, the Hydroxocobalamin bought from Germany is scanned in the post. Hydroxocobalamin deteriorates in light. Supplies brought in by wholesalers is brought on containers and "waved through" with paperwork. Another reason we should be able to purchase at the local pharmacy.

Bellabab in reply to newlandvale

B12 from Germany comes in cardboard boxes packed in some form of outer packaging. B12 can break down when exposed directly to daylight for perhaps a few hours but not from a quick scan by a light source of its packaging.

newlandvale in reply to Bellabab

Hi Bellabab

I am not a physicist nor do I have any sort of scientific background so my theory is simply a guess. I base this on the fact that although the B12 is always well wrapped when it is posted there is nothing to stop X-rays and X-rays can be more powerful and destructive than daylight. X-rays are powerful enough to get through our suitcases and destructive enough to limit their use in medical settings. I have looked into the suppliers and manufacturers of the hydroxocobalamin I buy from Germany and they seem legit. The X-ray theory is the only explanation I can think of to explain why so many of us need to self inject so frequently. Frequent injections into the same muscles is not ideal - NHS administering records which arm is used for this reason. We really need to buy our own supplies from a local pharmacy.

JanD236 in reply to newlandvale

I use partly nhs prescription supplied (from my local pharmacy) B12 vials and partly vials obtained from Germany. There is no difference in the efficacy of the two.

fbirder in reply to newlandvale

I have studied physics.

X-rays will pass straight through the ampoules without affecting it at all.

All of our B12 is imported. It is made in China or France.

helvella in reply to newlandvale

The X-ray theory is the only explanation I can think of to explain why so many of us need to self inject so frequently.

That could suggest anyone who has an X-ray would find much or all of the B12 in their bodies gets destroyed - especially after a CT scan. I have not seen any evidence of that happening.

Bellabab in reply to newlandvale

B12 can break down when exposed to sunlight. It does not break down from X rays applied for a tiny amount of time as in a scan. The reasons for frequent injections are not known fully. It is however due to the biochemistry in the body and is not in any way because it has been scanned.

Nackapan in reply to newlandvale

I also use NHS prescription .B12 and also buy from Germany.

So the one from thd local chemist is just shipped to them rather thxn directly to me .

If it were the cases we'd all be okay on thd regime thd NHS give us. Wouldnt need to buy any!

I so wish an xray was thd reason I need so many!!

newlandvale in reply to Nackapan

Local pharmacies buy from medical wholesalers who regularly ship bulk purchases in containers. They are "trusted traders" and don't get X-rayed.

X-rays are on the light spectrum but once the B12 is in our bodies it attaches to haptocorrin, intrinsic factor, transcobalamin II etc so is protected from both X-rays and sunshine. B12 is protected (stabilised) by the cyano bit of cyanocobalamin but unfortunately that does not work for me and the unprotected hydroxocobalamin seems far more effective. I self-inject into arm muscles twice a week but look forward to the NHS injection which I get every 8 weeks.

I do not have true pernicious anaemia involving intrinsic factor and doctors have on various occasions decided my symptoms are the product of hypochondria, over-imagination, malingering, addiction to B12 or an allergy to B12! My tendency to research on Pubmed doesn't go down well either.

I have recently been diagnosed with smouldering myeloma which is an early bone marrow cancer. As B12 and bone marrow are linked I suspect this is where my need for B12 lies. Hopefully I will see a specialist soon when this Covid dies down so I may get some answers then

Go by your blood tests. If folate low supplement. Women of childbearing age 400mcg daily.

A supermarket multivit perhaps

Just be careful not to over supplement.

I've just recieved my basic A-z multivit. Noticed it has doubled it vit A to 100% RDA. Used to be 50%

Now unsure I'd too much vit A??

Just when I tnkight I'd sorted my vitamin regime.

Packaging had changed but no indication 1 vit changed dose

helvella in reply to Nackapan

What matters very much regarding vitamin A is which form it is in.

So very often we see beta-carotene referred to as vitamin A. Really, it is a prohormone of vitamin A and needs to be split in two to form "real" vitamin A. Vegetables such as carrots, butternut squash and many others contain considerable quantities of beta-carotene but our bodies do not convert too much into vitamin A. But we can turn orange!

If it is preformed vitamin A, it is important not to overdo it.

Nackapan in reply to helvella

Okay thanks. Its annoying that the multivit has upped the vitamin A from 50% rda to 100%


You are wrong....

"While the liver contains about half of the B12 in the body,

it isn't in some kind of storage system. It is mostly

working B12, in mitochondria of cells making ATP from fats

in the Krebs's cycle to do all the work the liver does.

Most of the organs are high in B12. Then comes the

muscles. Mitochondria turn over at a given rate releasing

B12 into circulation for potential recycling. For it to go

elsewhere is possible if the muscle cells die and free up all

their B12. "

Nackapan in reply to Hidden

I've lost the thread . Whose wrong?

fbirder in reply to Nackapan

Supposedly, I am.

fbirder in reply to Hidden

What a load of old tosh!

The Kreb's cycle does not make ATP from fats, it makes ATP from Acetyl CoA, which can come from fats or carbohydrates.

All cells need to make ATP. The liver does not need more than any other organ, the brain needs to make much more of it. So why doesn't the brain contain more B12 than the liver? Because the liver stores B12. msdmanuals.com/home/disorde....

Mitochondria do not 'release B12 into circulation' whatever that is supposed to mean.

I have a degree in biochemistry plus 33 years experience as a biochemist. Do not tell me that I am wrong when I am so obviously not,


Feel free to copy my words and check internet. Some people just echo the official line.

fbirder in reply to Hidden

Feel free to stop posting complete garbage.

Hidden in reply to fbirder

Listen to your own advice. I'm not going to argue with you. Let readers make up their own minds. You've been reading the subject 5 years? Add twenty more, as I have, and open your mind. That's my final word.

Nackapan in reply to Hidden

Why are you hidden?

helvella in reply to Nackapan

When you see a user name of Hidden, it means that the person is no longer a member of this forum.

Nackapan in reply to helvella

Seems odd they can post then ?

helvella in reply to Nackapan

The person was a member at the time they posted. But they have since left the forum - and HealthUnlocked. At that point, the name on their posts changes from whatever it was to Hidden.

Nackapan in reply to helvella

But they posted under 'hidden' todaySurely of they have left they have left ! And should be ignored or removed or rejoin with a profile ??

Hidden in reply to Nackapan

Doesn’t work like that. Unless you delete your old posts before you leave, they remain under the name ‘hidden’ - ad Infinitum 😊

helvella in reply to Nackapan

They might have posted today. And one second later, they left.

(I have no knowledge of what actually happened. The same things would appear whether they chose to leave or were removed by HealthUnlocked.)

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