Pernicious Anaemia Society
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Recently diagnosed b12 deficient with questions

Hi All,

I was told by my doctor last week that I have B12 deficiency. I have been booked in for 3 injections over 3 weeks to be followed by injections every 3 months thereafter for the rest of my life. At the time I was just happy that he'd found a potential cause of my symptoms that I didn't think to ask any further questions (such as why am I b12 deficient).

I went to the GP with the following symptoms: lack of energy, frequent daily bouts of exhaustion, lack of motivation, aching joints, inability to remain focused, "clouded" thinking, depression, anxiety. These symptoms have been progressively getting worse over the last 4 years (maybe longer).

My first injection is this Friday.

I am posting now as I have numerous questions and don't know where else to get the answers.

What can I expect over the next 6 months?

Do the injections work? If so how quickly?

What else can I do, other than the injections, to feel better?

What information should I request from my GP?

What if I don't feel better???

Before last week I knew very little about B12 deficiency, other than B12 may help with dementia. Any help or advice any of you can give would be very much appreciated.

Thanks in advance,


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11 Replies

What was your level and do you have the results of any other tests? If you post them here you can get some help with other things you can do. Ask for a printout of results. Examples would be full blood count, iron studies, folate. If your B12 is low you should also have intrinsic factor and parietal cell antibodies checked.

The treatment regime your GP has decided on does not follow the guidelines for either treatment of anaemia or neuro symptoms. 30% people get only neuro symptoms rather than anaemia.

Everyone is different and responds differently. It is a matter of trial and error. Many people decide to supplement with high dose sublingual B12 or self inject with B12 bought abroad in European pharmacies. I supplement with sublingual metylhb12 from amazon 5mg per day and on 1mg hydroxyb12 from GP but finding I need it more often. Fortnightly seems best for me. Since going monthly my hair has started to fall out again, feel tired and some pins and needles (mild) are coming back. The B12 overall has made a massive difference to me and many others. I felt more awake and alive very soon after starting it. The other symptoms took a couple of months. Good luck!

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Thanks for the reply. I didn't get any further information from the GP - like I said I was just glad he'd come up with something, and I was also expecting it to be diabetes, so being told it was B12 deficiency caught me off-guard. I shall go back and get the full results. I will post them once I have them.

Thanks Again,


All the best- I would recommend educating yourself before you go and bringing someone with you who can support you if need be. Read Gambit's post here to get links to the guidelines

Posting your results will be helpful in getting more specific advice. Basically B12 does not work alone but as part of a B complex of vitamins within several biochemical reactions within the body. It works especially with folate in the methylation cycle so you need folate with B12 to get the best use of it, but really it is best to take some B complex too with B12. It is possible to overdose on pyridoxine so I just take B complex every time I take B12, along with methylfolate. Folic acid is a cheaper less bioavailable form of the vitamin which needs to be converted to be used. Some people have trouble doing this, which is why it can be better to take methylfolate. Methylfoalte and methylB12 are both available on amazon in tablet/sublingual form. Marre on the forum is very experienced and I think she recommended taking the other B vitamins around injection time. If you are low in folate though you will need it more often at least initially.

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Some books that you may find useful

Could it be B12? - Sally Pacholok et al

Pernicious Anaemia - the forgotten disease by Martyn Hooper

Its unlikely that you will get anything useful by way of information from your GP as they are generally quite unaware of what B12D really is.

B12 is only found in animal products so if you are a strict vegan or don't eat much by way of meat, dairy or fish then you will develop a dietary deficiency, which can be corrected by high dose tablets

Otherwise it is the result of something going wrong with the specialised mechanism by which most B12 is absorbed in the ileum. Things that go wrong include

- Pernicious Anaemia proper: your body produces antibodies that either kill of the specialised cells (parietal cells) that do the absorption, or destroy the binding factor that helps these cells absorb B12 (intrinsic factor). Your GP may want to test for antibodies to rule this out - probably IFA - but the test isn't very sensitive and is only about 50% accurate so a negative result doesn't necessarily mean you don't have PA

- lowering of acid levels in the stomach as you get older - which is one reason why it gets more common as you get older

- surgery affecting the ileum (eg gastric by-pass where the ileum has been involved in the bypass)

- genetic abnormalities in the ileum (which can be picked up through endoscopy

- drug interactions - ironically a lot of drugs that are used to treat early symptoms can also make the situation worse because they fall into this category - eg treatments for GERD such as omeprazole, NSAIDs such as ibuprofen, anticonvulsives (eg Gabapentin), antihistamines. Metformin used to treat type 2 diabetes also falls into this category though studies are a bit mixed because some show that whilst it may lower absorption it may also increase the bodies efficiency in using B12

Whatever the cause the treatment is the same

Once you have a problem it tends to accelerate as time goes on as the mechanism by which the body recycles B12 also involves the ileum.


Thanks for your reply (I didn't release I'd had more replies as my email notifications were going to my junk folder).

I dont think its my diet - I'm not vegan and eat red meat 2 or 3 times a week.

I have been taking 2 to 4 painkillers a day for the last 5 years or so to help relieve agonising arthritic pain in my neck and shoulders - sometimes NSAIDS like Ibuprofen but it's mostly paracetamol and codeine.

I have now had 2 b12 injections (on weekly basis for the first three), and I actually feel worse. My joints are really aching, my head is even more fuzzy and I feel exhausted all the time, whereas previously I would only start feeling like that from about 2 or 3 o'clock in the afternoon. I really hope that I turn a corner and start feeling better soon because it's horrible feeling like this (I am also a one man business and its severely impacting my ability to keep it going).

I did get the blood test results printed out but I don't think they were the full results. I'll go back and ask for them again.

thanks for the info and advice.

I also take anti-histamines during the summer to see off hay fever which can get very bad towards the end of the season. God, I sound like I'm falling apart at the seems :-)

Sorry that you are suffering - people sometimes do feel worse before things improve ...

If you can keep a diary of symptoms as it can be quite difficult to notice improvement.

Unfortunately it can take a while to feel better and really start to notice the difference.

I've managed to get some of the results from the GP:

Serum ferritin (XE24r) : 180 ng/ml [ 30 - 400 ]

Serum folate (42U5.): 5.7 ng/ml (< 3ug/L suggest deficiency)

Serum vitamin B12 (XE2pf): 116.56 ng/L [ 155.87 - 1,355.4 ]

B12 is the only one flagged as outside of range.

Hope this makes sense to someone.



Yes your folate is on the low side so you'd be best taking folate supplements to get the best use of your B12 which is low. Some symptoms can get worse before they get better, but you are not getting B12 often enough. If you have neuro symptoms it should be alternate days until no further improvement, then 2 monthly. If you have macrocytic large blood cell anaemia, it should be 3 a week for 2 weeks then 3 monthly. These are the guidelines in BNF.

Thanks for the reply. Are there any particular folate supplements that you can recommend? Can I take them in tablet form given that I can't take b12 in that way?



Hi yes methyl folate 400 mcg is available on amazon. It is easier to absorb other vitamins etc than B12. It is the biggest and needs to be actively transported across the gut wall. I also take B complex 50 for a day or two around injection time as all the B vitamins work together and I want to make sure I get best use out of my B12!

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