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Pernicious Anaemia Society
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Falsely high B12 levels with IF antibodies

Thought this paper was interesting - shows how hugely different serum B12 results can be just depending on the method used for the test and that having intrinsic factor antibodies can lead to an incorrect B12 level.


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Wow that was written 9 years ago, so the medical profession have known about this for some time!

I saw my GP on Thursday and asked for a trial of B12 injections. She point blank refused, as I am within "normal B12 levels." I mentioned, politely, that in the case of possible B12 deficiency they are guided to treat the patient with B12 injections if they are showing clinical symptoms of deficiency, regardless of blood result. She just shut me down and said they would not consider it.


Yes - getting injections from the GP seems to be difficult even when serum levels are low normal so I'm not surprised they refused. I know that I was extremely lucky. You could mention that you intend to self-inject if the GP will not prescribe?

Just been reading back through your posts - was your last ferritin level in October last year? Can you get it tested again just to see whether it has dropped? (This is something at my practise I can get just by making an appointment with a nurse - doesn't need prior approval by GP).

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Well, after yours and other comments on here recently I asked my Endo if he would add ferritin to my thyroid blood test form and he kindly did. I had the blood test at the hospital last thursday morning first thing, so will hopefully get the results later this week.

The Endo said he could not ask the GP to prescribe B12 injections based on my blood results. He also suggested I explore my MTHFR for any defects prior to going down the B12 route as he said there are different types of B12 and it may be that the wrong one could harm me or at least not make a difference. So I ordered a private test which has arrived, been done and sent off. But I've got to wait a long time for the results.

GP has long since written me off with anxiety and insomnia and just keeps telling me I need to deal with these and that will cure my exhaustion. I've said until I'm blue in the face that these issues are brought on by how unwell and exhausted I feel. The anxiety is much reduced now because I don't do much/go places to get anxious about, and the insomina is not classic insomnia, it's just cr*ppy sleep. If that makes any sense?

Oh dear sorry I've gone off on a moan a bit there haven't I! Sorry, just trying to explain GP situation.

How are things with you now? Feeling any better?


Thank you Laura5,

There's a lot of interesting articles and research on B12. Just wish some of the doctors i've seen had read more about it.

Exhausted Lee,

I've been ill for over 15 years, bad experiences with GPs. In the end realised that the only person who would help me (apart from the kind members of HU) was myself.

I self treat with B12 but it was an absolute last resort. I have improved but suspect i have some permanent damage.

I noticed from a thread on the thyroid forum that you take pregbalin. Some drugs for epilepsy can affect the uptake of B12.


I've written some detailed replies on other threads that may have useful info for you.


Hi Exhaustedlee,

Sorry to hear that the GP refused. The NHS should be following the "BCSH Cobalamin and Folate Guidelines"

In my opinion, it's a document that's well worth reading and I plan to give a copy of it to my new GP. I found page 29, a diagnosis flowchart very useful.

Some GPs are not aware that this document exists.

I have found the PAS useful to talk to.

pernicious-anaemia-society.... 01656 769467

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Hi Sleepy Bunny

Thank you, yes I've tried the PAS only last week actually. They did kindly call me back, but they just told me to get the GP to prescribe B12 injections. But they won't do it so I'm at square one with that really. I mentioned to the PAS guy about self injecting from the internet but he said they "wouldn't condone that, as you don't know what you're getting"

I am awaiting latest thyroid and ferritin blood results and also have just done a load of private tests including my genetics, chronic fatigue, cortisol. Once I have all of these (and analysed them!) I'll hopefully be in a position to do something about things.

I started taking apple cider vinegar last week and some other magnesium based supps so that will hopefully help with absorption issues and energy levels. Although no difference yet.

Thanks for your message. I hope things are good with you.


Thanks fot that---Very enlightening! Why don't our G.Ps know about this?

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Thank you for this. This is extremely important information. Sadly, I must continue to be proactive in my own healthcare, as the medical community has failed to 'take care of my health' 95% of the time.


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