Can somebody explain the science of the 6 loading doses of B12 hydroxocobalamin as advised by NICE & BNF and concentrated over a two week period?
To me it makes more sense to spread these out at 1 a week for 6 weeks, or maybe 2 in first week and then 1 a week.
I am basing this on idea that by time of treatment body has been slowly starved of B12 for several years, that it can only store so much in the liver (or is it in the muscle from an injection?) and that it only use so much at any one time.
Or is there a specific reason to try to rapidly elevate B12 in the blood quickly?
It would be interesting if this strategy of six 1000ug loading doses is used in all similar countries, not only the UK
Thanks
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Springblossom13
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Are theses NICE and BNF guidelines part of British national health guideline? If so why some GPs in Britain don't follow that? Really is there any statistical study regarding following these guidelines and clearing neuropathy in people with nerve damage? Please someone help me to understand that. And why pills can't work like injection?
If you are starting on treatment in the UK for B12 deficiency and are not being given 6 injections over 2 weeks as a loading dose, you should quote the NICE guidelines.
I have read lots of different things, and search the internet and you will find many things about B12 orally being as good as injections. There is no definitive answer, and different countries & people recommend different things.
My view from what I have read is that many studies do show that if you take large doses 1000 to 2000 ug of B12 daily this can be as effective as injections. However given that there could be questions marks about absorption, the safest thing to do is provide injections, especially were clear neuropathy is involved at the start of treatment. Still from what I read I would feel fairly confident B12 sublingual (a form of oral) would be just as good as injection.
Sometimes symptoms are not clear cut. For me I have a variety of symptoms. I think headaches, chest pains and a few other things could have neurological elements. They may or may not be caused by the B12. And I can only give my own experience which relates to my own case.
I am trying sublingual tablets and b12 injections spread out with a week apart for first 5 weeks, though I had 2 at the start with a day in between to get me going. Whilst it helps having clear guidelines and standards, sometimes it could be helpful to flex this to meet how individual patient responds. From a NHS point of view they may prefer a single approach is taken, since this is tried and tested, plus easier to implement
I have been doing reading on the forum and elsewhere to find answers. Some complaining they were not given the loading doses. So I should think myself lucky that they offer this to me and told that NICE guidelines should be followed
Still again I feel the a store of B12 has probably been depleted over many years, so it makes sense (to me) to replenish it somewhat gradually, to allow the body to get use to it, absorb and store it more easily it.
Presumably there is only a small amount of B12 which is used at any one time and it requires other components to do it is work, so there is a risk there will be insufficient of them in a 2 week period
So one injection of 1000ug to a B12 body must do a huge amount of good, however why have the subsequent ones so quickly afterwards?
I guess just want an explanation as to why the loading doses makes sense. The beauty in biology is that most things make sense. I am not yet understanding the sense of the loading doses
I totally agree with you, and think that it is this pattern of suddenly flooding the body, when it has been used to being so frugal, that sometimes causes it to break down and then need high/frequent doses for ever in some people.
It goes against all my animal nutrition principles.
The Dutch seem to have done a lot more research into B12 more recently than elsewhere in the world and I believe their protocol is 1 injection a week for 6 weeks, with 1 to 2 monthly boosters, and if I could turn back time I would definitely prefer that regime for my treatment, as to me there are more than enough molecules of B12 per 1ml injection to easily supply a body with frugal mechanisms for a week and a gradual, gentle, week on week, supply would steadily top you back up. I think you should then be monitored for symptoms and a pattern established so you could aim to be dosed again 1 week before your symptoms returned - or at least at the immediate onset of any symptoms recurring!
But I am not a medic and have no documentation to back up what I am saying. With decades of successful nutrition experience though, I have not just pulled my ideas out of thin air either.
Thanks for suggestion about Netherlands. I found this:
"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."
Just shows that I'm not just barking! I was as convinced that I'd read it as much as I know I'm dreadful for not storing links to my knowledge sources and properly referencing them. Oh to be as well organised as Helvella!
I will save this one though, while I think of it! Thank you!
I think the logic behind dutch guideline is not to disrupt daily life since in some people high frequency of injection causes a pause in daily life. We need to walk everyday in order to induce pulses in damaged nerves and it helps nerves to revive faster as I think Schwinn cells repair small axon nerve cells based on demand so when induced pulse in nerves happens due to any physical activity along with proper supplements can help nerves get repaired faster. Maybe I'm wrong but mild electrical muscle stimulator helps nerves get repaired.
Walking sounds like a sensible idea. 1 injection a week is general is easier to fit. Still either way, there seems little research done to suggest benefit of one protocol or another. However if deficiency is big and symptoms equally pounced the intensive treatment sounds better. The most important thing seems to be not to leave permeant damage i
The same thing is done with low levels of vitamin D. High doses are given to get the body up to an optimum level quickly rather than slowly increasing. I think Nackapan logic is probably right
I think biochemistry of B12 and nerve repair is so complex and even may be different based genetic and this problem should be addressed completely based on trial and error in order to find the best individual solution.
The body normally (ie no deficiency) contains 2-4 mg b12, or up to 5-6 mg. Only 30 % of a 1000 mcg hydroxycobalamin injection is retained, so six loading doses should add an estimated 1.8 mg.
I suppose the idea is to increase the level of b12 in the body. I'm guessing because biochemical processes in the body depend on a certain concentration of a substance. If you have zero b12 you're not helped much by adding one daily requirement a day, you need to get the levels up first.
That is logical thinking and makes sense, thank you.
But the body does have mechanisms for being frugal on low amounts and I think that this should be taken into account more.
I get a sense that it is people who have been deficient for a long time who are more likely to need more frequent injections going forward but I might be entirely wrong - or it might be the duration of deficiency that somehow breaks the mechanisms for uptake, retention and use within the body, rather than any specific loading dose reaction.
I wonder what percentage of people on each protocol need high level doses/frequent jabs for life? It does seem to be more of a problem in the UK on the 6 in 2 weeks regime but there are bound to be other factors affecting the prevalence of reporting.
I've tried to get several students interested in doing some research for us all but haven't had any takers yet.
The idea behind loading doses is to flood blood with B12 so that cells get a large amount of B12.If you have a B12 absorption problem you are no longer able to use the stores in the liver that the body normally uses to maintain B12 levels at the point that is right for you, which means you are totally reliant on the amounts in your blood. This is because the mechanism that is used to release the B12 relies on the same mechanism that allows you to absorb B12 from your food, which means that you can fill up the stores but most of what is released just passes through the gut without being absorbed back into your blood.
The rate at which B12 is removed from your blood is generally greater the higher the B12 levels are so loading shots are an attempt at balancing this higher rate of removal and keeping B12 levels really high.
different countries have different protocols and use different forms of B12 - in the US loading regimes vary considerably because there aren't any standards and can even be different at different hospitals in the same city - weekly is a common practice.
To clarify, if there is a B12 absorption problem (such as in PA), then the liver is no longer used or able to store B12?
Simplistically, I had imagined the B12 loading doses was to replenish the B12 store in the liver. Maybe sometimes this is the case depending on the cause of the B12 deficiency
more that the role the liver plays is no longer that relevant.It is, in theory the case that a shot would resolve a B12 dietary deficiency, or one that has been due to a treatable absorption problem - such as tapeworm - once the problem has been treated.
I did find a couple of blog posts on B12 Deficiency Info website which weren't about loading dose patterns, more about typical patterns of maintenance injections (UK treatment).
Has two patterns of treatment, one for those without neuro symptoms and one for those WITH neuro symptoms, Both patterns allow for maintenance injections to be given every 2 months.
Blog posts that discuss typical UK treatment of 3 monthly maintenance injections.
As a result I decided to have an initial 2 loading doses with a day in between, and then have the following 4 injections at one week intervals. To achieve this I have just said this is the only time I am available.
In between the injections I will be taking semi daily between 1000ug to 2000ug sublingual B12 first thing in morning - or sometimes have a dose first thing and second dose mid afternoon to spread out blood levels.
As the injections are so effective I wish to optimise them by making sure I give my body sufficient chance to have the other required co-factors. And it is not to say sublingual is not effective, I just wish to make sure I am spreading out benefit in case one working better than another
Obviously this is different to NICE guidelines but I have not found anything to back up them up and many countries do it differently. Also I do not have major neurological symptoms. If I did have this I think the NICE guidelines of continuing alternate days of B12 injections make sense.
I'm sure when I was first diagnosed with PA, around 12 years ago, my loading dose was 1 per week for 6 weeks, then 1 per month for 6 months, then 1 every 12 weeks. Not sure if that was the NICE guidelines at that time or whether my GP had his own guidelines. I live in Central Scotland.
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