Update - had to go to A&E yesterday

I stared to feel very faint, and got pins and needles all down the right side of my body. My husband was really concerned (and I was getting a bit scared too, started wondering if I was having a stroke, and I'm only 46).

I saw two doctors, who did lots of tests of my reflexes, co-ordination and sensitivity. They ruled out a stroke, thank god, and said my symptoms were most likely due to my B12 deficiency. The first doctor was going to give me a b12 injection, but then managed to view my GP records on the computer, and noticed that my last blood test (20 Dec) showed my B12 was just back into the normal range, but commented that I may need to be 'normal' for a while ,before the symptoms stop. This is interesting though, because it means that the cyanocobalamin tablets I was taking (from the doctor) seem to have increased my B12 levels, so I assume this is good news as it rules out an absorption problem?

The hospital did another B12 test while I was there, and said my GP should be able to access this. I was feeling quite a lot better by this time, and thankfully they allowed me to go home.

So I will be back to see my GP next week, although as the b12 supplements seem to be working, I'm not sure if she'll do anything? But in the meantime I've started taking the Jarrow Methyl B12 lozenges 1000mcg. I'm going to take two per day to give myself a boost.

23 Replies

  • PS - can someone confirm that 2 X 1000mcg per day is a safe dose, I don't to overdose by mistake.

  • Sorry, just one last thing: I took 1000mcg this morning, and had another 1000mcg about an hour ago. It may just be coincidence or wishful thinking, but I think I feel less foggy/woolly.

  • You can't overdose on B12.

    Hydroxocobalamin is used to treat cyanide poisoning - dose is 5g of hydroxo administered intravenously over 15 minutes with a further 5g 30 minutes later if needed. That is 2500 times the dose that you are taking.

    How long have you been taking the methyl. It's more likely to be the methyl that has raised your levels if you have been taking it for a while rather than the lozenges you had from your GP.

    1% of B12 is absorbed outside the ileum so very high doses taken by mouth (and the doses you talk about with the methyl lozenges would fall into that category) can result in enough getting through for some people - though it doesn't work for everyone.

    You really need to know exactly what your B12 levels were and exactly how significant any increase was. To be honest you might think that they knew something about B12 in A&E but I, personally would be a bit more sceptical without knowing exactly what your levels were. B12D isn't something that can be treated by looking at the serum levels and treating on that basis.

  • I have been taking 50mcg cyanocobalamin tablets, twice a day, for three weeks - this took me from being very slightly low, to just back into the normal range (sorry, I don't know the exact figures). I only started taking 1000mcg lozenges today. my heart's been racing a bit since I took this evening's 1000mcg lozenge, and that's what made me wonder if I was overdosing.

  • Hi Petal

    I see you're on the Thyroid site too & say you felt fine 'til your GP reduced your hormone meds - this can cause a racing heart as can low iron cause palpitations - I'd go back to the GP and get more Thyroid TFT tests (with TPO ab) and ask for an increase in Levo, and ask for other vital mineral tests too.

    Chances are if you're low Thyroid and low B12, you'll probably be low in other vital minerals too - any deficiency must be eliminated to feel well.

  • Well spotted Spareribs! But I've now had two thyroid function tests, and all the results came back to my dctor's satisfaction - and my b12 was tested at the same time, and it was that result that was low (not my thyroid). Each blood test was a full blood count, so I assume anything else would have been picked up?

    I only started taking the 1000mcg lozenges today, and two hours after taking the second lozenge, my heart started pounding (not had that before) but Gambit posted to reassure me I hadn't overdosed. However my heart rate now seems to be ok again, and strangely I'm feeling quite a lot better. I assume this is just a coincidence though, as surely 1000mcg lozenges won't improve me quite so quickly?

  • my doctor was satisfied with my thyroid tests which were 10.2! Also, if your B12 was under the level and you have been having neuro symptoms they should be treating you with injections. The tablets the doctor gave you may have raised that level slightly but it doesn't mean they have got to where they should.

    If I were you I would request a copy of your results to see exactly what your levels are, something I wish I had done.

    There is a good group on Facebook with lots of helpful information re B12 called Pernicious Anemia/B12 deficiency support group.

  • If I use the sublingual spray I get an almost immediate effect (couple of minutes), with the sublingual lozenges taking a bit longer to provide good relief from the symptoms.

    OK this is extreme, but it'll give you an idea of how safe B12 is...

    I was using 5000 mcg sublingual tablets / lozenges, as well as the spray, and was talking up to about 10 a day, on top of my daily 1000mcg jabs. (Now I have found some 1500 mcg jabs I don't need the sublinguals).

    If I manage to get more than enough B12 into my system, with supporting supplements, to eliminate my symptoms, the only "side effect" I get is micro acne. I don't like it, obviously, but it's not as bad as any of the deficiency symptoms and goes as soon as I reduce my B12 intake.

    There are people around the world that have been taking higher doses than me for years and years to gradually improve the damage they sustained by being long term B12d.

    I hope you find something that suits you so you continue to improve! :-)

  • I think the Dr at the hospital should have given you the B12 injection.

  • He was going to do that Frodo, til he accessed my GP records, and found that I just back within the normal range. He then took another blood test from me, sent it up to the lab, and was going to base his decision to inject on the results when they came back. But he then went off duty, and the next doctor I saw said the b12 result wouldn't be back til the following day. And as they'd ruled out a stroke, I was then referred van to my GP.

  • I understand what happened, but an injection might have helped and would not have done any damage. As you say though, it's good that your levels have increased somewhat with the tablets. I hope your GP is helpful and you continue to improve!

  • As Gambit has already said, you cannot overdose on B12 and, with those neurological symptoms, it is essential you are treated frequently to avoid permanent damage. Cyanocobalamin tablets would not be adequate alone. When treatment begins, many people experience an aggravation of symptoms as though nerve endings are coming to life.

    "The BNF advises that patients presenting with neurological symptoms should receive 1000 ug i.m. on alternate days until there is no further improvement".

    Re. B12 serum test levels, below is the latest BMJ research document (bottom of page 4 under, "How is response to treatment assessed") :

    "Cobalamin and transcobalamin levels are not helpful because they increase with vitamin B12 influx regardless of the effectiveness of treatment and retesting is not usually required".

    In other words, once b12 treatment is started, the serum blood test results are not reflective of how effective the treatment is, as it does not measure whether B12 is being absorbed by the tissues. It is the clinical condition of the patient that is important.....


    The research document is supported by many research papers and is peer reviewed.

    I hope you feel better soon petal02.

  • Polaris - I agree that the cyanocobalamin tablets alone would not be enough, but as they appear to have nudged me back into the bottom of the normal range, do you think this is why I had all the pins and needles, you said that when treatment starts your nerve endings start to react?

  • These tests are never exact, there is always some uncertainty. In some of the assays we used to run at work we would accept +/- 5%. But that was using super-expensive and accurate equipment. The immunoassay they use for B12 probably isn't as accurate. Especially as it will be affected by the presence of anti-IF antibodies.

    So two successive readings, one just below the lower limit, one just above, could quite easily represent no change at all. It's only when the change is large (mine went from 85 to 5999 - but that was excessive) that you know things are moving in the right direction. Most people would say your levels want to go from a hundred-and-something to around 500 to 1000.

  • I think it all really depends on whether or not your body can use what's there. I've just realised that the hydroxo injections I get from the doctor can't be used in my body. I have been taking methyl skin patches 3times a week which makes me feel much better. However after my recent injection in December, I had to start supplementing with the patches again within 2 weeks. My levels were high at 899 and the doctor said "you can't possibly be feeling bad"!!

    Please be careful of doctors going just by blood test levels - they obviously don't tell the whole story.

  • This is an interesting extract (second letter on page 2 of BMJ rapid responses) :

    " Is it important which form is used in treatment? In most people, it does not matter. They can convert cyano- and hydroxo-cobalamin into the active forms needed. However, I have recently reported a case in which it did matter. The severe vitamin B12 deficiency, including dementia and psychosis, responded to treatment with high dose oral methylcobalamin, but not to equally high dose oral hydroxocobalamin. [1]

    1. Rietsema WJ. Unexpected Recovery of Moderate Cognitive Impairment on Treatment with Oral Methylcobalamin. Journal of the American Geriatrics Society 2014;62(8):1611-12 doi: 10.1111/jgs.12966[published Online First: Epub Date]|."


  • Sorry softpaws, what I was trying to say was that Cyanocobalamin tablets are not the most effective supplementation - methylcobalamin is usually better absorbed into the tissues and for alleviating neurological symptoms between injections (see reviews on Jarrows Methylcobalamin 5000mcg, on Amazon)

    Serum B12 test will show high B12 levels with any B12 influx (tablets or injection) but this is not an indication that it is necessarily being absorbed into your tissues.

    Many medical practitioners do not realise this and it is often the reason why patients are not being treated adequately. It might be a good idea to show the BMJ document to your GP.

  • I really appreciate all the responses. I'm encouraged that the 1000mcg lozenges are already making me feel better. I really hope my GP will give me injections, if not, I may see a different doctor (there are 6 doctors at our practice, so I could see someone else quite easily).

  • No problem Polaris, just goes to show that one size does not fit all and we all have experimentation to do. Don't know how ill I would have been if not for this site and everyone's input. Thank you all. 😊

  • I have found I only feel better after getting my levels over 1200!

    How are your folate, ferritin and vit D levels?

  • Given the events of the past few days, do you think it's likely the doctor will now try injections, or am I likely to have a battle on my hands?

  • once you're supplementing a blood test won't give a true picture, you have to go 4 months without supplementing I was told by Hampster1 (I never could). GPs daren't treat if bloods indicate 'normal' levels - however Dr Chandy did & made a lot of people better! (before he got into trouble).

    You could try taking some evidence to your GP (there's lots of B12 guidelines/research papers) he might listen, also s/he may take note as GPs HATE us going to A&E. Good Luck. J :D

  • Hi,

    I gave my GP a copy of the "BCSH Cobalamin and Folate guidelines" and a copy of Marty Hooper's latest book "What You Should Know About Pernicious Anaemia and Vitamin B12 Deficiency"

    After many years (over 10) of being highly symptomatic for B12 defic I may finally be getting somewhere.

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