Pernicious Anaemia Society
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Some advice please

After my original post and all the help and advice that I received from this site, I took the plunge and decided to self inject. My doctor has been very supportive and is supplying my needles and syringes.  I have been reading on this site about the necessity of taking Folic Acid to help the injections do there job properly. So, went back to my doctor and suggested taking Folic Acid. She said good idea. She gave my a prescription. On reading the enclosed leaflet it states - do not take Folic Acid if you have Pernicious Aneamia or another condition that causes B12 deficiency.  So I am now very confused. Any advice from anyone would be greatly appreciated. Thanks in advance. Bethx

6 Replies


Perhaps your GP can explain. See  Management section in link below which might be part of the reason. I have read that treating a folate deficiency without treating a co-existing B12 deficiency can cause problems. I think taking folate can sometimes mask macrocytosis caused by a B12 deficiency.

I am not a medic just a patient who has struggled to get a diagnosis.


Yup, Sleepybunny is, as usual, correct. Folate supplementation when B12 deficient is a bad idea unless B12 supplements are being taken.

Unless you get your prescriptions free you might be better off buying folic acid from the supermarket, where they're less than 1p each.

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Brilliant!  Well done! 

It is important to supplement with B12 first and then folate because, as the others say, the folate can cover up your B12 symptoms and the B12 is essential but once the B12d is sorted it is important to then add in folate so your body can metabolise the B12.  Folic acid is good, easy to get, cheap and works for many people so try that first but be aware that some people find they do much better on methylfolate.  (I've just found this).

Please also make sure you get plenty of a broad spectrum multivitamin and mineral supplement plus extra potassium and magnesium.  These will all be needed to metabolise the B12. 

I hope this helps but come back to us if you have more questions!  :-) 


Thanks to Denise, sleepybunny and fbirder for your replies. I have been having B12 injections for over a year now. Despite the doctor saying to me after my blood test that she had never seen such a low reading she did not suggest anything other than injections. Where I am now has very much been me suggesting things to the doctor. She has prescribed Folic Acid tablets, I am in Scotland so prescription is free. I will now start taking them. I still think it is slightly strange that the information leaflet says not to take if you have pernicious Aneamia 

Thanks all again.



I know, it is confusing Beth.   As others have mentioned above, it would be better to avoid taking folic acid whilst your levels are low. There is an excellent film on the B12 deficiency site with information on this:

Haemotologist's quote:

"If you treat someone with B 12 def. with folic acid, you can either precipitate neurological abnormalities or, if the patient already has neurological abnormalities, you can make them worse. So folic acid should never be given empirically unless the B12 status is normal."

"High levels of folate are normally okay as long as your vitamin B12 level is also normal. Cells need vitamin B12 to use folic acid and when vitamin B12 levels are too low, folic acid cannot be used and builds up in the blood."

If there is concomitant vitamin B12 and folic acid deficiency then vitamin B must be started first to avoid precipitating subacute combined degeneration of the spinal cord. In patients with isolated vitamin B12 deficiency and anaemia, additional folic acid supplementation is recommended until vitamin B12 is replete, to prevent subsequent folate deficiency after replenishment of B12 stores.


Sincere apologies for taking so long to thank you for taking the time to respond. I am still undecided about taking the folic acid. Going on holiday next week so I think I will wait until I come home rather than risk something new. Thanks again for the information. Beth


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