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Pernicious Anaemia Society
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Low b12

Hi what should your b12 levels be after the loading injections ? My level was 170 before injections and went up to 550 after injections , I haven't had any injections since the (every other day ones) and my level is 423 .... my doctor is saying this is a normal level

My ferritin was 11

And folate was 4

Haemoglobin estimation 12.4

Can u be cured after loading injections and not need anymore?

Any help and info would be great as I hear that doctors are not informed enough about b12 defiencys

Thank u

18 Replies
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Hi DutchessVS you don't say how long after your last injection the test was done.

Your Folate is on the low side. Have you been supplementing with folic acid?

Have all your symptoms "disappeared"?


Hi clivealive sorry they tested me again about 4 weeks later , doc says folate normal ?

My ferritin level was 11 which they said was low so was taking ferrous fumarate which brought my level to 22

I'm feeling better than I was but still not quite right and very tired

Thanks for replying πŸ‘πŸ»


If you are in the U.K. "normal" treatment for B12 deficiency is loading doses of Hydroxocobamalin 1mg every other day for two weeks or until there is no further improvement in symptoms and the maintenance injections every three months.

If you still have neurological symptoms you need to make a list of them and present this to your doctor and ask him to treat you according to your symptoms and (perhaps) even start you on loading doses "until there is no further improvement" according to the N.I.C.E guidelines below. Click on the link, then on "Scenario: Management" and scroll down to "Treatment for B12 deficiency"


If possible take someone with you who can validate your neurological symptoms as the doctor is less likely to pooh pooh you in front of a witness.

It is also important that your Folate level is monitored as this is essential to process the B12.

There is a complex interaction between folic acid, vitamin B12 and iron. A deficiency of one may be "masked" by excess of another so the three must always be in balance.

Symptoms of a folate deficiency can include:

symptoms related to anaemia

reduced sense of taste


numbness and tingling in the feet and hands

muscle weakness


Folic acid works closely with vitamin B12 in making red blood cells and helps iron function properly in the body

I am not a medically trained person but I've had P.A. (a form of B12 deficiency) for more than 45 years.

I wish you well


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Hi clivealive yes I live in the U.K. And I had loading doses ever other day for 2 weeks , then after testing me 4 weeks later my levels were 550 so told me to test again 6 weeks time which I did and was 423 my next app with doc is tuesday

Thanks for replying


Your doctor should be guided by your remaining symptoms not by what he is seeing on his computer screen


clivealive thanks so much


an injection of B12 puts a lot of B12 into your blood and would put your levels off the measurable scale. After that it will then start to reduce over time (mainly as kidneys reduce excess but a little as your cells use B12). How long this takes varies from individual.

After loading shots serum B12 isn't a particularly useful test for managing B12 absorption problem because the fact that you have had a shot introduces another factor that means the normal range is no longer applicable, so treatment should be based on symptoms not on B12 test results.

How long ago did you have your loading doses?

B12 injections are not going to cure a B12 absorption problem which is a problem in the gut. Some absorption problems are curable (h pylori, worms) but others aren't (PA, Coeliacs, Crohn's).

If the reason for B12 deficiency is curable then the absorption problem is cured and further injections (may) not be necessary as the patient will be able to rebuild their B12 stores in their liver and access them.

However, if the absorption problem isn't curable, then the patient may be able to temporarily rebuild stores but won't be able to use more than a small % of those stores because the mechanism for accessing them relies on the same mechanism that is affected by the absorption problem. Regular top-ups will be needed.

As raised serum B12 can cause a reaction that hinders the transfer of B12 from blood to serum and this seems to affect a significant number of people, the average serum B12 level that is needed by patients who have had loading shots is much higher than that for a normal population (around 1000pmol/L). For this reason serum B12 post loading shots cannot be used to determine whether a further shot is required.


Hi Gambit62 i had my loading doses in December

The nurse that gave me my injections told me I had P.A and that I'll need injections for the rest of my life , but my doctor told me that I didn't have P.A ..so confused

Thanks for replying


did you have an IFA test? if it came back negative then your GP may be using this as justification for saying that you don't have PA - however, would be wrong to do so as the test is not very sensitive and results in false negatives 40-60% of the time so a negative is a long way from ruling out PA as the cause of a B12 deficiency. The BCSH guidelines refer to 'IFAB negative PA' as a result of this.

If you had h pylori they should have treated you with antibiotics. Unfortunately GPs tend to be rather low on knowledge and understanding of B12 deficiency and B12 absorption problems (though they often don't realise this) and there is nothing like someone who is confused to make you feel confused.


Hi Gambit62 havent been tested for h pylori

Yes I'm sure I had IFA test and sure they said was all ok

Only started asking for printouts of my test results the last 2 times but I'll ask for others on Tuesday to see wether the IFA test came back negative or not

My doc said that my haemoglobin level was fine at 12.4 so not anemic

Thanks so much for helping


the lack of anaemia - which i the case of B12 has nothing to do with haemoglobin levels though they might be a bit raised - doesn't rule out PA either as the anaemia is an historic misnomer because a couple of centries before B12 was formally identified PA was first named as a type of anaemia that lead to co-ordination problems, madness and death. However, we now know that it is a problem in the gut that stops you absorbing B12 and it is B12 deficiency that causes the anaemia etc. 25% of patients don't have anaemia (macrocytosis in which red blood cells are larger and rounder than normal) isn't present in 25% of people who present with B12 deficiency.

Was the GP that you spoke to the one who first did the tests that identified low B12. If not then suggest that you talk to the first GP rather than the one who is telling you that you don't have PA.


No it's the same doctor

But seeing a different doctor on Tuesday as the last doctor has just finished her training and is moving on πŸ˜–

Should I ask for mma testing on Tuesday ?Gambit62 I've read this is more accurate?


MMA is an expensive test and may require referal to a hospital

Think you should really focus on getting proper treatment - ie not using B12 levels to determine frequency of treatment.

If you are UK based then make sure that you refer your GP to the BCSH guidelines and ask to be treated in accordance with those - which means maintenance at least 3 monthly - if you have problems with pains and feeling in hands and feed or other neurological symptoms then it should be every 2 months.

Your GP can access the guidelines (if UK based) through the BNF and they can also be found here


if they are also a trainee then suggest they take a look at the are of the PAS website that is aimed at helping medical professionals improve the diagnosis and treatment of PA and discusses the issues with treating B12 absorption problems on the basis of serum B12 levels.



Ok thanks so much Gambit62


Hi my levels were 169 before loading, and 3 days later when checked for folate which 3.0

B12 was 2000 so fairly high, but I read that the liver only hold so much at a time, and it goes down quite quickly,hence follow up shots, I can't absorb b12 through my stomach, so having injections at the moment 8 weekly, but feeling a lot better, except for my tingly feet, apparently can take a long time to go, or sometimes never.

Hope you get sorted.



Hi Tricia2747 ok thank u that's good to know Defo going to get this sorted now that I've learnt more about it πŸ™‚

Do u know the reason why you can't absorb it Tricia? Have u got P.A ?

Thanks for replying


I have been taking omeprazole a PPI for reflux for years, this stops acid production, and absorption of b12 I've had my pariet cells tested but came back neg, not pa, but my folic levels low at 3.0 trouble is folic acid makes me feel sick,I'm not a big veag eater,but am trying to sort my stomach out with Probiotic caps daily I also suffer with IBS, so am dealing with that too. I knew nothing about b12 deficiency until last Nov, it does explain why I've felt rubbish for so long,this site is great for info. after my last 8 weekly injection a week ago,deff feeling better.more energy.good luck. Duchess vs


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Ok glad u feel better thanks so much Tricia2747


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