Pernicious Anaemia Society
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B12 level

Hi I had my b12 done again last week , it came back at 337ng, which I think I low, ferritin was 86 folate 10.8. Heamacroit was low at .364. esr was raised again been like this while, vitimin d was,

In June b12 was 100

September 406

In November 500 something,

Now February 337.

Had loading doses in June and then 2 injections 12 weeks apart next one due march 12. But I think it should be higher by know,any advise,

7 Replies

Hi Ozzie,

It would be good to keep your serum B12 higher if possible, I like to keep mine over 350, which I achieve by injecting every 2 weeks cyanocobalamin and every 2 months hydroxocobalamin. In your case it seems going to once every 2 months would be good if you are on hydroxocobalamin B12. Some will say get serum over 1000, all very nice, but not every one can achieve that.

I hope this helps,

Kind regards,



Hi Ozzy. Your vitamin D is low and also your B12, according to this extract from the book, "Could it be B12? :

"we believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".

"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."

According to your earlier posts, you had pin and needles, etc. BCSH, UKNEQAS and NICE guidelines, all recommend treating neurological symptoms urgently regardless of tests and many GPs are ignoring them or not aware of them! If you still have these, you should be having injections every two months at least or until no further improvement.

You will see from the above document that all patients with anaemia, neurological symptoms or glossitis, and suspected of having PA should be tested for anti intrinsic factor regardless of cobalamin levels (although, as you will see below, this test is not always reliable!) It is in this document, that the BNF recommends that patients with neurological symptoms should receive 1000 ug i.m. on alternate days until there are no further improvements......

It might be also worth just pointing out to GP the summary points of the latest research document Cmim BMJ- A.A. Hunt B12 :

Cmim/BMJ document. " Summary:

* Vitamin B12 deficiency is a common but serious condition

* Clinical presentation may not be obvious thus leading to complex issues around diagnosis and treatment.

* There is no ideal test to define deficiency and therefore the clinical condition of the patient is of utmost importance."

* There is evidence that new techniques, such as measurement of holotranscobalamin and methylmalonic acid levels seem useful in more accurately defining deficiency.

* If clinical features suggest deficiency, then it is important to treat patients to avoid neurological impairment even if there may be discordance between test results and clinical features.

Severe deficiency shows evidence of bone marrow suppression, clear evidence of neurological features and risk of cardiomyopathy.

It is important to recognise that clinical features of deficiency can manifest without anaemia and also without low serum vitamin B12 levels. In these cases, treatment should still be given without delay."

If you have problems getting more frequent injections or the cause of the deficiency, I found supplementing with Pure Advantage sublingual spray or Jarrows B12 5000 mg effective.


People vary significantly in how they retain hydroxocobalamin ... let alone using it ... something that the treatment regime in the UK fails to recognise so what is probably happening is that the level goes up for a short time after the injection but then quickly starts to drop off again, leaving you with quite low levels in a short time. It may still be in the 'normal' range but it does show that you are not retaining B12 very well and should really be higher, but the only way that is going to happen is if you have injections more frequently (or find another way of supplementing.


Hi Ozzie,

I am not sure if your vitamin D is too low or not as ug is not the usual units. The 2 commonly used units for measuring vit D levels are ng/ml (commonly used in the US) and nmol/l (commonly used in the UK). To convert ng/ml to nmol/l you simply multiply by 2.5. If your vitamin D result was 24 nmol/l then you are deficient and you need to be supplementing asap. Anything less than 50 nmol/l is deficient. If your result was 24 ng/ml then this converts to 60 nmol/l and you are not deficient and you do not need to supplement.

Do you have the results to hand? Can you verify what units were used?


Hi it is in ug but someone told me it's the same as ng, thanks


ug/L (micrograms per litre) is the same as ng/mL (nanograms per millilitre)

So, while a single microgram is one thousand nanograms, it is true that the numbers will be the same for both ug/L and ng/mL.



Vit D in the UK is usually expressed as nmol/l but for USA divide by 2.5 to get ng/ml (see grassrootshealth). - our 125 is their 50, optimum - see I can do math even when poorly - it's all in the fingers! test here if GP won't - (£28 now)

B12 deficiency needs baseline Vit D - according to my surgery anyway unofficially .... awkward I know.... J x


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