Do other medications interact with b1... - Pernicious Anaemi...

Pernicious Anaemia Society
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Do other medications interact with b12 injections

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My mum's b12 level were at 274 last year, she went on to have a TIA. I think it ws caused by years of taking metformin. Her GP refused to give her trial of b12 injections but gave her a private prescription of 5 viles of b12. My question is, is it safe for her to take b12 with the medication she is currently on? Metformin, omeprezole, clopidogrel are the main ones I'm concerned about. Can she have an adverse reaction does anyone know?

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clivealiveForum Support

Hi Lyndsay80 I am also on Metformin and Lansoprazole and have been for many years whilst having had B12 injections since 1972 so there's no problem with your Mum having the injections.

It's more a case that the above medications are known to have an adverse affect on B12 levels than the other way round.

Do you know if your Mum's Folate level is OK?

I'm not medically trained but have had P.A. for 46 years.

I wish you both well

Hi clivealive , thanks for your response yes I thought it was that way around, but thought I'd double check. She apparently isn't anemic, but has low iron stores of 6. However she can't tolerate the iron supplement they put her on at all, there was a mention of having it by drip in hospital but it was never followed up.


Link about "What to do next" if B12 deficiency suspected.

Is your mum symptomatic for B12 deficiency?

B12 Deficiency Symptoms

pernicious-anaemia-society.... (may need to be member to use this))

Risk Factors for PA and B12 Deficiency


UK guidelines suggest that people who are symptomatic for b12 deficiency should be treated even if B12 levels are within range.

Has your GP read following UK B12 documents/articles?

UK B12 documents

BSH Cobalamin and Folate Guidelines

Flowchart from BSH Cobalamin and Folate Guidelines

BMJ B12 article



Unhappy with Treatment (UK info)?

Letters to GPs about B12 deficiency

Point 1 is about under treatment of B12 deficiency with neuro symptoms

Point 5 is about being symptomatic with an in range B12 result.

CAB NHS Complaints

HDA patient care trust

UK charity that offers free second opinions on medical diagnoses and medical treatment.

B12 books I found useful

"What You Need to Know About Pernicious Anaemia and B12 Deficiency" by Martyn Hooper

Martyn Hooper is the chair of PAS (Pernicious Anaemia Society). Book is up to date with UK b12 guidelines.

"Living with Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Has several case studies.

"Could it Be B12?: An Epidemic of Misdiagnoses" by Sally Pacholok and JJ. Stuart (USA authors)

Very comprehensive with lots of case studies.

Is there any family history of PA (Pernicious Anaemia) or other auto-immune diseases? May be worth joining and talking to PAS if PA is suspected.

PAS (Pernicious Anaemia Society)

Based in Wales, UK.


PAS tel no +44 (0)1656 769717 answerphone

PAS support groups in UK


B12 Deficiency Info website

UK B12 Blogs

There are stories on both these blogs about older people with B12 deficiency.

Martyn Hooper's blog about PA

B12 Deficiency Info blog

Blood tests


Full Blood Count and Blood Film

Folate Deficiency

Coeliac Disease

NICE guidelines Coeliac disease recommends that anyone with unexplained B12, folate or iron deficiencies should be tested for Coeliac disease. Has your mum had both tests below?

In UK, two first line tests are recommended.

1) tTG IgA

2) Total IgA

My experience is that Total IgA test is not always done but I think it's an important test as people with IgA deficiency will need different tests for Coelaic disease as their bodies will not produce the antibodies tested for by tTG IgA test.

NICE guidelines Coeliac Disease (2015 version)

Coeliac Blood tests

H Pylori infection

Any surgery involving nitrous oxide as part of anaesthesia?

Nitrous Oxide

Some parasite infections eg fish tapeworm can lead to B12 deficiency.

Access to Medical Records (England)

Neurological Consequences of B12 Deficiency

Untreated or under treated B12 deficiency can lead to further deterioration including spinal problems.

PAS news item


Help for GPs

1) PAS has section for health professionals.


2) Leaflet "An Update for Medical Professionals: Diagnosis and Treatment " available to PAS members only. Some forum members have passed this to GPs.

pernicious-anaemia-society.... See Page 1 of leaflets.

3) I gave my GPs a copy of Martyn Cooper's book ""What You Need to Know About Pernicious Anaemia and B12 Deficiency".

I hope your mum gets the help she needs.

I am not medically trained.

Thanks for all that info Sleepybunny. We have PA in the Family. Her mum was on b12 injections, she also has lupus. I also need them but never get given enough, i cant tolerate gluten yet they say no reason why, its just by choice? and yes she's symptomatic. We both took tests on the b12 society website and it sys we're in need of it due to symptoms alone. She's been deteriorating and it's worrying me immensely. I'll read through all the info you've sent. But her gp is not great, they were abusive to me when I went on a trial of b12 as I ws very symptomatic and levels were at 237, i improved, then they decided to take me off it, so I contested it. They actually told me to leave the practise. So I moved. They've been very similar with my mum, hence giving her a private prescription of b12 but won't administer them Nd told her not to ask for more.

Hi Lyndsay80

Have you considered self-injecting? Many of the people on here, including myself, self-inject. Also, many actually need more frequent injections that the 2 or 3 monthly ones the Medical Profession seem to think are sufficient.

It's relatively easy to get the B12 injection, syringes and needles etc and not expensive. If you are interested, let us know on the forum and we can help you find suitable websites for ordering the supplies you'd need.

in reply to JMN2017

Hi JMN2017 I already am self injecting.. I'm asking for my mum's medication as she didn't wnt to self inject in case it interfered with her medication. She's waited and waited to see if Dr will help her but they won't.

in reply to Lyndsay80

Apologies Lyndsay80

However, as B12 injections don't interfere with medications, would you Mum consider self injecting - just a thought.

Well done for self-injecting, yourself ;)

So sad the HPCs are so ignorant re treating B12 def/PA, eh!!!

in reply to JMN2017

Yeah ignorant is one word for it 😏 Im quite proud of myself as im petrified of needles, but needs must. She is considering doing it as getting nowhere with Dr herself. We contacted and they agree she should start injections. I'm trying to convince her to start asap, but she's a bit concerned as we go abroad for a few days, Thursday to Sunday and she's worried in case she feels ill with it. As body adjusts to it. I think she's better to start sooner with a couple of injections this week but she's not sure.

in reply to Lyndsay80

Yes, I agree with you. She might even feel better after a couple of injections ;) There's little chance of her feeling worse than she is already, with only a couple of injections, surely?

If you can't persuade your mum, then there's little you can do, really. I don't suppose it is likely to make that much difference if she prefers to start injections once you're back. She's presumably waited for some time already.

Anyway, good luck and well done for helping your mum. Once she's more confident re the injections and feeling the benefit, she'll be so grateful to you.

So sorry you don't like needles etc. How do you manage to self-inject? There are some auto-injectors available, but seemingly expensive, which I 've heard people with needle phobias find helpful.

Have a good, relaxing time abroad, if you can. Think of us in all this heat!!! I'm in East Anglia and it's been incredibly hot today, and set to be even hotter tomorrow. I'm off to the coast, Felixstowe, tomorrow, with a friend so should be a bit cooler there :)

in reply to JMN2017

Yes we will see.. its upto her. Well im just a mind over matter kind of girl . My mum did 1st couple of injections for me, then I just didn't want to keep depending on others so I just take my time. I use intermuscular needle for better results. I need it, as if I leave it a bit too long, I get pins and needles in my arms and legs and start of acne.. So faster I get the b12 in my body the better it is for me. I use very thin needles so less painful if at all and inject really slowlyinyo my mid thigh. Hardly feel it most of the time. Get bit panicky at times and feels worse when my symptoms are bad but I just make myself do it. I don't have a choice in my eyes and the benefits far out weigh the fear.

Thanks we're on a hen do so going to be a bit mad with 24 of us. Hope you enjoy your break and the coast provides a nice breeze. It's been stuffy here in Manchester all day πŸ˜“


I think you're very brave doing IM injections. I do SubCut, using abdomen (plenty of it ;) ) I started by doing IM injections, with blue needle but I found it difficult to keep my thigh muscle relaxed so I changed to subcut, using orange needle. I find it very much better and easier. Apparently, there's no proven/documented difference in whether IM or SC is best, nor if the absorption rate differs.

Yes, looking forward to feeling the sea breeze tomorrow ;) Have a great hen do over the weekend. Umm, no time to relax then ..... ;)

in reply to JMN2017

Really.. maybe I'll switch, then I won't have to hype myself up so much. I use a yellow needle it's pretty thin. I read IM got into your system faster than SC.. it's always worked pretty fast for me but I've nothing to compare it to. So is it just a regular needle but doesn't go as deep?

Nope no resting time.. We have an itinery πŸ˜‚πŸ˜‚

Hi Lyndsay80

Yes, I thought IM was faster into your system but apparently not. However, once I'd had a few doses of B12, I didn't feel I needed to get it into my system particularly quickly so SC seemed better, and easier, for me.

I use the Orange needle, 5/8" and go in at about 45 degrees, so only going into about 1cm depth. I suspect your Yellow needles are finer than the Orange so just be sure not to go in too deep. I would think 1/2" depth would be about max. Might be worth just checking the depth for SC, in case I'm wrong.

Like I mentioned, once you've got B12 in your system, I don't think it matters too much how quickly it gets into your system. Certainly easier access ;) Check out YouTube if you're not sure, of course. Good luck. I'll be interested to hear how you get on ;) Send me PM if you wish, anytime ;)

Thanks for that info, I'll look into it.. Although I've found up to now I need 3 weekly injections as a rule. I have quite an active job and I've noticed the more energy my body uses the more b12 I need. I was knocked of my bicycle by a van last month and felt horrendous since. I tried weekly injections but this week I'm doing 2 injections as I've gone 2 weeks and my pins and needles have come back again and onset of acne along with fatigue in the mornings and mood swings as I'm not sleeping very well. I also find my symptoms can come on quite quickly, when my body experiences extra exertion, whether that is additional exercise or my body recovering from said accident, so I feel I do need the injections to work faster for me or I can't function properly at work or in general. So depending on my lifestyle, sometimes I need to go back to loading dose stage if that makes sense.

in reply to Lyndsay80

Hi Lyndsay80

I understand B12 isn't toxic. It's water soluble so we just wee it out ;) So that's one less thing to worry about. Also, several on this forum need B12 injections much more frequently and on long-term basis. Everyone is different. It may be that you need injections alternate days, every 3 or 4 days etc. Only experience will tell you what's best for you.

So, what I'm trying to say is that maybe you are one who needs B12 at very frequent intervals, ie just days apart. If that's what keeps you well, then 'go for it'!!! ;)

By the way, that's just my opinion, based on what I've learnt along the way. In no way is it 'professional' advice as I'm not qualified for that ;)

in reply to JMN2017

JMN2017 yes I agree.. it's trial and error to see what works best for you. Only you know your own body well enough. My Dr keeps trying to tell me it's toxic and can cause cancer.. I told him from my own research I believe it to be water soluble and therefore can't see how it can be toxic. He's hard hard work if I'm honest. That's why I self inject.

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