Pernicious Anaemia Society
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Does anyone know if taking high dose folate and ferritin will affect active b12 test?

Hi, I'm new here. Long story short- I've been sick a while now. I'm 26, and when I was 15 I had my first migraine with aura. Over time I had them more and more, and four years ago I had to stop working because I was having them almost daily. Finally I found out about homocysteine, and begged my doc for a b12 panel. I was right- low ferritin, crazy low folate and b12 'normal' at 220. Anyway, he's happy to keep throwing ferritin and folate at me, and agrees that I've probably been low all my life (symptoms I've had from infancy were miraculously cured- asthma gone, purple hands and feet now Daz white, and my acne also disappeared!) but he won't talk about the b12 and he won't test for PA because I'm in the normal range. I'm convinced it's PA- and it turns out my great granddad was diagnosed and had shots all his life. I have almost every symptom. My aunt had a b12 panel and got exact same results.

Problem is, my doc has had me going in regularly with new problems (all of which are on the PA list- most recently hallucinations, numb/tingling hands, fainting and weird balance problems) and he thinks I need counselling to help me come to terms with the fact that I may never find an answer.

When he said this I actually cried, which didn't help.

I don't need therapy, I need a doctor. I've printed off a bunch of helpful stuff I've found on here which I think will help him understand about b12 levels and convince him to send off for an active b12 kit in london, if not I'll save and have it done privately. But anyway, my question is, does anybody know if my high dose folate and ferritin will have any affect on this test? I've been taking it a couple of months now.

And if I do have the tests privately, will the NHS accept them? I can stretch to the active b12 and the intrinsic factor if I have to, but there's no way I can afford private treatment.

Sorry for the life story, but I'm quite worried, the numbness and the vision loss are starting to make me panic.



8 Replies

As far as I understand it, folate supplementation can mask a B12 deficiency. That's why they are so worried about fortification of cereals, and folic acid in pregnancy. I had low folate and active B12 of 256 and almost died of suffocation, having had all the symptoms you describe to that point. The auditory hallucinations were spectacular. At night the world was populated with spectres floating out of my field of vision. Surprisingly, the first B12 jab cured all the neuropsychiatric problems. It's taking longer to get my physical health back as I became unable to walk. But it's all good. I am prescribed hydroxocobalamin every other day on the NHS and folic acid 5mg daily. Plus D3. That was found to be low. I am privately prescribed methylcobalamin, too. Better for nerve damage. But... Sorry to depress you but I was forced to go privately for all my testing and diagnosis. The NHS doctor had to follow their findings. A GP can't ignore the opinion of a senior consultant, private or otherwise.

If I knew what I know now then, I would just have gone straight to the Internet for injections. Doctors police B12 as if it's platinum or diamonds. They know nothing about it, and do not like to be told. Well at least mine don't! And they have no accurate guidance from NICE or the NHS. A recommendation about B12 in CFS advocates waiting for macrocytosis before treating with b12. This small, ignorant note must be imprisoning, debilitating and ultimately killing hundreds of patients.

There is a way out of your problems, but sadly it requires either money to pay for a sensible opinion, or great fortitude in fighting for your rights as a patient. The Perncious Anaemia Society is great. They will surely have suggestions, and I know they are working flat out to get NHS guidance updated. Good luck. Keep us posted.


Your doctors ignorance is tantamount to negligence and he is slowly killing you. If he is unprepared to get properly informed then you may need to do it for him.

Regardless of poor guidelines from NICE it is basic medical knowledge that treating low folates with folic acid will mask the indicators of B12 deficiency in the blood tests. All the while the neurological damage continues in the background.

Add to that that the serum B12 is a poor test of deficiency in the first place - even before starting folic acid supplements.

I suggest you research as much as you can - a good book is 'could it be B12' and then write to your GP giving him the facts and insisting you are put on B12 injections. The main site of the PA society had lots of information too.

It is disgraceful that patients have to go to these lengths to educate GPs but you just can't let this go.

From what you say it seems you know in your heart this is B12 deficiency and your symptoms along with family history adding to the risk factors and other related deficiencies screams out you are right.


Well Bets

You seem to have the same problems many have encountered before you, sadly including myself. Now you have reached "Brickwallitis" you only have very limited options, in particular, because also like many in today's world, you have not won the lottery and therefore funds are low.

Firstly you can put down in a report form all that you have stated above, together with any and all the research you can find on this and any other site. Go back to your surgery, firstly making an appointment with the Practice Manager. Present to him or her, the facts as you see them, preferably in writing. Ask with all due respect that he/she requests that the content of your findings is placed before all of the doctors in the practice. Then state you will return for an answer to your request for full and further testing, including Intrinsic Factor, Parietal Cell Antibodies, HoloTC (Active B12) and if necessary MMA testing.

Secondly you must request a referral letter for Guy's / St Thomas's Hospital in London addressed to Dr. Dominic Harrington. Ring Denise O'blien, Dominic's P.A. first and get the full details. 0207 188 7188 is her direct line number.

Next return in 14 working days to the surgery for your answer. If it's a big fat NO! Then explain that you will very reluctantly, be left with no option, other than to be taking this to your local health board, for their evaluation. And then if necessary, to the Health Minister Jeremy Hunt. Do not be afraid to make waves, or kick ass, at this point, you have little to loose and you can always change your Doctor. In the meantime, simply request that you be referred to a Consultant in Haematology at your local main hospital, you will probably find that the Consultant may well see thing rather differently.

Hopefully, your G.P. will think again and wonder is it all worth the agro, especially as he has to now go through evaluations, according to Pulse reports as I read them.

You are allowed to have I.F. and P.C.A. tests on the NHS and your G.P. should know that Serum B12 tests are useless on their own and have already put these into the pipeline Serum levels are almost a waste of time and money. The HoloTC test will cost you about £18 at the last count plus £12 for the postal kit. Sadly if needed the MMA will set you back a further £98, always assuming your G.P. will not support you of course.

OR! you could simply try another Doctors in your area ????? The question is, will they be any better ??

OH! and by the way, Folic Acid dose mask B12, that is well documented in the medical world.

So good luck, hope all this helps to give you food for thought and you soon find the solution and get to feel well in a hurry. Best wishes B12 Turbo


Hi everybody, thanks so much for your replies, I really appreciate it!

I've been reading up, bought the book, joined the PAS. All of this was invaluable, and once I got over the shock that a lot of symptoms I had been dismissing are in fact evidence of neurological damage (my arms have been wasting away for over a year, my feet won't walk right, my incapable hands- four years ago I got an illustration degree and now I struggle just to grip a pen right, and most scarily my vision loss) I'm ready to go round two with my doc. I'm really hoping to get a diagnosis, because if I'm right, half my family have this too, and my little nieces are showing signs that I did when I was young.

I'm fighting for the active b12 in london first, but as I understand it up to 75% of serum b12 can be inactive, and you need folate to convert it to active b12 in the first place. So my level of 220 was obviously no good if I had no folate. No wonder I kept collapsing.

Anyway, I'm hoping if I can present it logically he might do the tests for IF and PCA, if only to get rid of me.

I have thought about changing doctors. Unfortunately mine is, believe it or not, the best of a bad bunch.

If my symptoms worsen I'll self medicate, but I'm also wondering if a private appointment might get me a diagnosis? My doc will probably be willing to prescribe shots if someone else writes him a nice letter supporting the idea. Does anybody know any specialists around Somerset (UK) that are more knowledgable about PA? And willing to treat symptomatically? I have a feeling that my folate and ferritin supplements might have screwed what would have otherwise been a hugely definitive homocysteine test. Anybody know how long folate stays in your blood?

On another note, I felt so much better initially on the folate I came off my migraine meds and I have been migraine free for almost four weeks. Last time I missed a migraine med I had three full attacks the same day, so this is HUGE. It's not perfect, and I can feel them coming back a little, but I think with B12 my migraines may even go completely.

I guess everyone here knows how frustrating the whole thing is...

Thanks for the help, I'll be pestering everybody with questions over on the PAS site soon, so see you there!



That B-12 level is not normal .Very low in range perhaps , if he passes comments about counselling and cognetive

training tell him not to be insulting . Ive been there , if you have an ulcerated mouth and raw tongue ask your

Dentist, mine got me a referral to Maxillio Facial and a diagnosis of P/A . However if you cannot survive on 3monthly injections you may still have to buy and inject yourself , I need a min of 1000 B-12 level to survive , that

is injecting every 14 days .

The NHS is completely broken run by experts with a commercial interest .


NHS is as good as privatised but many people did nothing to stop it while others have campaigned. I guess too busy watching X-factor!!

As for extra injection, contact and ask for vial. That's where I get mine. No import duty!!


Folic acid supplementation can mask the megaloblastic signs in a full blood test but does not change the measured B12 level.


I bought a active b12 test from blue horizon and did pin prick test at home .


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