Pernicious Anaemia Society
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Often symptomatic despite regular treatment - where to go from here?

I was diagnosed with PA in 2010 and following administration of the loading doses was commenced on initially 12, then 10 and now 8 weekly injections. As the 8 weekly allowance might imply, I have a sympathetic GP who is willing to allow more frequent injections due to the fact that my symptoms are often still apparent despite having the injections.

Now whereas I am truly grateful to have a GP who is willing to prescribe more frequently, especially when I read how so many individuals struggle with this issue, I am getting somewhat frustrated by the fact that I still remain symptomatic despite having my B12 more regularly than most. Unfortunately, the injections seem to make very little difference, and I still suffer with brain fog, dizziness, aches, pains & fatigue on a fairly regular basis. At times the tiredness is almost crippling; my body feels like lead and sometimes I will get in from work and go straight to bed. This doesn't occur daily, and I appreciate that these symptoms are nowhere near as bothersome or severe as what many others may experience, but they are unpleasant nonetheless.

I have mentioned this to my GP on several occasions during the last three years, and despite her willingness to acknowledge my symptoms and prescribe more frequent B12 injections, I feel as though have a met a bit of a dead end so to speak. By now I have ceased mentioning such issues during appointments as I feel she is reluctant to fully address the issue, and simply claims that I "would feel worse" without the B12. I don't doubt that there is some truth in that statement, however couldn't help but feel somewhat fobbed off. And to some extent I can infact counteract that theory, as truth be told, for a variety of reasons, I went some 10 months last year without an injection (I know; very naughty; but now back on track) and can honestly say that I felt exactly the same as I did both prior to diagnosis and while receiving regular treatment. I just feel the same whether I have an injection or not.

And so I was wondering where to go from here? I am intent upon having one last try with my GP during my next appointment, but to be honest I don't hold much hope on this one as she was sloppy with the initial diagnosis anyway (she claimed that there was no point in retesting my B12 level despite knowing that it was low, and only investigated and eventually diagnosed PA after I had a blood test elsewhere which revealed a deficiency) and hasn't actually tested my B12 levels at all since diagnosis and commencing treatment. I might catch her on a good day, but failing that, what else can I try? Despite possessing a generally positive outlook on life, I can't help but feel a tad dejected regarding this at times. I am only 30 years old, have a healthy BMI, eat a well balanced diet (ironically containing a lot of B12!) and exercise regularly; I really don't think that I should be feeling like a snail on valium for much of the time!

Apologies for the very long post, but I don't know anybody else who has the same condition and am therefore glad to be able to discuss these issues with a community such as this. Many thanks to all who read this, and any advice would be gratefully received.

13 Replies


Welcome here. If you are not doing well on your current treatment (even if it is a very king GP and you are getting B12 injections regularly) then you need investigations done as to why. Other (B) vitamin deficiencies such as folate can occur during B12 treatment and if not addressed then you will not metabolise the injected B12, or other problems like thyroid issues could play a part so really you need further investigations, more frequent B12 injections is obviously not doing it for you.

I hope this helps,

Kind regards,



In (uncharacteristic :)) defense of your GP she is right that there isn't any point in retesting your B12 levels once you have started treatment as you are being stuffed so full of B12 and the test that is given doesn't distinguish whether it is the form of B12 that you really need ... and certainly doesn't look at how your metabolising it and processes at that level.

Marre is very right that it would be wise to look at other possibilities - as well as looking at potential interactions with other deficiencies.

On a personal note - would have to say that the injections, on reflection have been a bit hit and miss for me - don't think I really noticed any difference in the first 9 months after diagnosis but then I was just given the diagnosis and shots after a fall had me hospitalised and someone picked it up in blood tests ... so didn't really have a clue what it really meant and how it was affecting me until I really started looking into it about 10-12 months after diagnosis. Went through a really bad patch at the start of this year when I was getting colds and any benefit I might have felt from the shots disappeared within days on one occasion rather than weeks. Tried talking to my GP about it but he just wanted to put me on anti-depressants so I hobbled back home ... ranted, howled and decided to try other ways of supplementing. I ordered some shots from Germany but haven't actually started using them because I had noticed that when I used a nasal spray the fog was a little less intense ... so decided, whilst waiting for the shots to arrive ... to try using bigger doses of that ... and it does seem to have worked for me. When I went to see the GP I was struggling to get up, to walk, to think. I'd played bowls a couple of days before and was so exhausted afterwards that I missed tea because it took me that long to change out of my bowls shoes. I was miserable, depressed, not coping with any stress and really finding it difficult to be around people. Two weeks later I was looking a lot better, starting to talk to other people, and felt quite comfortable going up a step ladder and perching at the top to prune my grape vine. People around me have noticed the difference. Now it may all be psychological, and even I'm a bit skeptical at the proposition that a nasal spray would be more effective than an injection but ... after my last shot I laid off the nasal spray for a few days but found myself starting to struggle with my mood and people again quite quickly so don't think I'll be doing that next time. Not saying stress is a thing of the past (just had a couple of bad days pre-menstral madness ... but would still say that wasn't on the scale of how much it would have affected me a year ago).

All of which is a long winded way of saying that B12 isn't a one-size fits all - however much the medical text books and medical practitioners want to believe it is - and may be you need to experiment a bit for yourself.

You need to be a bit careful because of interactions with other vitamins (potassium levels can, I believe, be affected by having a lot of B12 in your system). Know I was struggling a bit with feeling tired last weekend - and had been craving a banana but not had it a few days ago so had a banana and followed that up for a few days and that seems to have righted things.

I do hope that you manage to find a solution that works for you. Ideal would be to work with your GP if you can but totally understand if that is feeling like too much.


I just have to say that in some cases it is helpful to test serum B12 whilst on treatment as it can show up diminishing levels as in my case. On standard B12 treatment my serum B12 levels dropped every year, to a level that became very marginal (B12 230 ng/L = 170 pmol/L.) and gave me the reason to start to look into my treatment, and to start to learn to self inject etc. Had I not done that I'd not be able to do much by now I'm sure! Marre.


Thanks Marre - useful to know ... but just wish that you didn't here so many people saying that GPs had stopped treating them because serum levels had shown an improvement and were back in reference range ...


Yes I know what you mean, both my daughter's have had GPs decide they could stop treatment as their levels were now good..My serum B12 levels are tested every year to see if I comply as I self treat. I find it very useful as I can see (besides feel) what reducing and or adding does to my blood over the years, as I do play around with my B12. But I know its common to find GPs stopping treatment, particularly if serum levels are well over the ref range of normal.


A high B12 serum level in itself does not cause hypokalaemia (low potassium). The danger period for hypokalaemia is at the beginning of B12 treatment as the rapid increase in the B12 level stimulates the growth of new red blood cells which puts increased demand on a number of factors, one of which is potassium.

I see little point in testing blood serum B12 once treatment has started as blood serum B12 is not a reliable indicator of anything at all and an elevated B12 level just gives ignorant doctors the opportunity to reduce or even discontinue treatment. What matters once treatment has commenced is whether the symptoms of B12 deficiency are improving.


Hi Engels,

In principle nothing is that black or white with B12 it seems, there is some justification to test serum B12 as a first line to see why someone is not doing well on current treatment. Although you are right many GPs seem to think a high serum B12 level is a reason to stop treatment there is as much of a chance that the serum B12 is lower than expected and further investigations would be warranted. There are more like me who found after testing serum B12 whilst on (years) of standard B12 treatment, useful as in it showed low, to low for some one on standard maintenance B12 treatment. But you are right it should include taking symptoms into account. Not every one on B12 treatment achieves high serum B12 levels, in my family there are few that can get their serum B12 over 500, let alone near the 1000. In my case I know now (some 12 years after diagnosis of PA) that I do not recycle much (if any) of the injected B12 (via bile).

Kind regards,



Thanks Engels for the reassurance over the B12 and potassium though I may actually be in the period when the B12 levels are building up ...

I think there is a family history on my mothers side of periodic low potassium anyway so it could just be that - definitely get cravings for bananas at times :)


Why don't you check Active B12, see what is happening at cell level.

Also, have you considered having your Vit D checked.

You could remind your GP very tactfully, that you had to organize your own blood test, that you felt she wasn't interested in your health ( tactfully ) that she is your GP, and you felt let down by her approach to you.

She will of course disagree with you.

Then I would ask her, at this point, if its not too much trouble, and how you would really appreciate it, if she could organize this list of blood tests, for me, please.

I am sure she will be falling over backwards to help you.

When you approach her in this way, she is on the back foot...she should be very willing to do anything for you....

You can only but try, but be firm with her, she does deserve it from you.

Good luck and look after yourself.


1 like

Thanks everyone for all of the input, and sorry it's taken me so long to reply!

Well, I saw my GP and mentioned the tiredness for the umpteenth time. She checked back on my previous blood results, and noted that my thyroid and iron levels have consistently been good therefore there's little point in retesting at present, which makes sense.

She says that there is no logical cause for me to be feeling tired as my diet is good, and as mentioned above my iron and thyroid are being well behaved. However, in all fairness she has elected to administer my B12 injections more frequently i.e 6 weekly instead of 8 weekly which I appreciate and am really hoping that it does the trick. I have literally wasted the weekend sleeping, and this morning could barely get out of bed in time for work, which, well... sucks, really.


Hi cls84 ,

You do not mention serum folate..B12 needs folate (and other B vitamins) to metabolise and visa versa, so if you are low on folate then extra B12 is not going to make a difference. But its good your GP will allow more frequent B12 injections for you so perhaps find out if serum folate was tested and OK, plus taking a good ( over the counter) multi vitamin helps as so many (B) vitamins need each other to be metabolised. If you give a lot of one then demand on the others will increase and its important to try to keep some balance say.

I hope this helps, and that the extra B12 injection will help you,

Kind regards,



Hi Marre

Thanks for your reply.

She didn't mention anything about folate, but nor did I ask so I will make a point of mentioning it when I next see her.

I am somewhat 'on the fence' when it comes to multivitamin supplements, as theoretically I should derive all or at least most essential vitamins and nutrients through my diet, which is very healthy & balanced 99% of the time... honest! But then again, if my body can't absorb B12 then who knows what else it has decided to reject, and I did go through a phase of taking them so I guess it won't do any harm to start again. It worked out at a cost of 8p a day so I doubt it will break the bank!

Thanks again for the advice :)


I so am with you, I'd rather eat what I am deficient in, I also eat very healthy, organic if poss etc, but I know I just do not take things up, so best to get a good multi and just take it. They will all be balanced so not something that will further upset your bodies natural balance. You can ask for copies of your blood tests then you can see what has or not been tested. Also if you keep a file you can see over time what changes and what not, all worth it I think. Its worth looking at your MCV; If you are B12 and or folate def then your MCV (-size of blood cells ) will increase, If you are iron def your MCV will decrease, but if you are iron and or B12/ folate def your MCVF will be normal size. You will see that on copies of blood tests. Quite often when you are marginal blood test wise you are told all is fine, but you can help your self by seeing how near a deficiency you are, and addressing it as best you can before it actually registers def and you feel horrid, well you can but try anyway! Marre.


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