What are the risks of B12 injections? - Pernicious Anaemi...

Pernicious Anaemia Society

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What are the risks of B12 injections?

Alesia profile image
26 Replies

Hi all I've been told by my GP that there are risks involved with B12 injections such as Cardiac Arrhythmias and potassium depletion.

Does anyone have any info or experience of this please?

I'm sure she was meaning well but now I feel scared

Best wishes

Alesia

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Alesia
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26 Replies
fbirder profile image
fbirder

The only danger is the same danger as for the first exposure to any injected substance - anaphylactic shock. That's the reason why we always recommend that people's first injection be done by a medical professional, who would have access and training if such a rare event occurred.

I've never, ever, heard of B12 causing cardiac arrhythmia.

If you have megaloblastic anaemia, caused by low B12, then B12 injections can kick off a burst of red cell formation that can deplete potassium stores for a couple of weeks. Easily fixed by eating potassium-rich foods and no worse that the potassium depletion that happens when one loses a lot of weight quickly. And I bet she doesn't recommend that patients shouldn't try weight loss in case of potassium depletion.

Your doctor is full of it.

ITYFIALMCTT profile image
ITYFIALMCTT in reply tofbirder

fbirder Do you sometimes wonder what bizarre Chinese Whisper or GP equivalent of playground wisdom was distorted into clinical gems such as 'B12 causing cardiac arrhythmia'?

fbirder profile image
fbirder in reply toITYFIALMCTT

Like other people, they are prone to taking partial information, from unreliable sources and making unjustifiable extrapolations.

That's why we hear things like 'cyanocobalamin is dangerous because it contains cyanide' and 'methylcobalamin is better absorbed / more natural / doesn't need converting / etc.' And 'in Japan everybody with a B12 below 500 is treated' and 'having MTHFR means you need special supplements' and ...

Shebacat123 profile image
Shebacat123 in reply tofbirder

Hiya

In your opinion, which type of B12 do you think is best for injecting ?

I am confused by the information that i find on the internet

Many thanks

fbirder profile image
fbirder in reply toShebacat123

In the UK it would have to be hydroxocobalamin. In the USA I would go for cyanocobalamin if hydroxocobalamin was too difficult to find.

Shebacat123 profile image
Shebacat123 in reply tofbirder

Thank you very much for that info <:)

Alesia profile image
Alesia in reply tofbirder

Thank you all info very helpful x

clivealive profile image
clivealiveForum Support

Hi Alessia after 46 years of B12 injections every four weeks (making a total of over 600) I'm still "clivealive" and kicking.

You cannot overdose on B12 as any excess is excreted via your urine and as fbirder suggests eat something like a banana to "keep your doctor at bay"

Alesia profile image
Alesia in reply toclivealive

Thank you "keep your doctor at bay" made me giggle!

clivealive profile image
clivealiveForum Support in reply toAlesia

That's for when apples are out of season :)

Alessia profile image
Alessia in reply toclivealive

I will keep that in mind. Thank you :D!

Sleepybunny profile image
Sleepybunny

Hi,

This link mentions possible side effects from hydroxycobalamin injections which NHS uses in UK. it does say that the frequency of side effects is not known which to me suggests they are not very common.

bnf.nice.org.uk/drug/hydrox...

I have not had any noticeable side effects from B12 injections.

Perhaps PAS (Pernicious Anaemia Society) would be able to point you to more info on possible side effects?

pernicious-anaemia-society....

PAS tel no +44 (0)1656 769 717 answerphone

Alesia profile image
Alesia in reply toSleepybunny

Thank you this is really helpful x

deniseinmilden profile image
deniseinmilden

I have suffered from cardiac arrhythmias for over 30 years and have had a couple of operations to try to cure them. I have had B12 deficiency symptoms for almost all of that time.

I have done about 800 injections over the last couple of years and since doing so my arrhythmias have just about disappeared (I can't remember the last time I was aware of it). Many other people have found the same so maybe your Dr got things back to front and should have said that B12 cures some arrhythmias or that a deficiency causes arrhythmias.

You can get short of potassium (please Google this to find out about it) but this can be corrected through your diet by eating potassium rich foods and, if necessary, carefully using a little LoSalt.

Not getting your injections gradually damages your body. If you need them, you need them.

You may need other supporting supplements to make the extra B12 work properly and it is possible that you could benefit from a broad spectrum multivitamin and mineral supplement plus extra folate, potassium and magnesium, maybe iron.

Go for it and start to feel better soon!

Alesia profile image
Alesia in reply todeniseinmilden

Thank you this was really helpful and has put my mind at ease x

Alesia profile image
Alesia in reply todeniseinmilden

I have palpitations and strange fluttery heartbeats all the time which is really unnerving! I don't really know what cardiac arrhythmia is but maybe that's what im experiencing anyway?

deniseinmilden profile image
deniseinmilden in reply toAlesia

Sounds just like some of my symptoms - all gone with plenty of B12 and supporting supplements

Alesia profile image
Alesia

Thank you everyone for taking the time to respond, it's very much appreciated.

I don't know for sure if I have B12 deficiency, I've been so ill for a year now with many of the symptoms but all my tests say normal, so it's taken me 6 months to finally persuade my GP to give me a therapeutic trial of B12 injections as neither she nor my consultant can tell me what's wrong with me even after extensive tests. I do know I have Gastritis and SIBO which explain the gastrointestinal symptoms but I have tingling hands feet & face, hair loss, huge weight loss, dizziness, sore tongue, anxiety, depression ... I could go on!

Just so glad GP has agreed to try it at last! Even if there are some scare tactics going on!

clivealive profile image
clivealiveForum Support in reply toAlesia

Please ensure that your doctor also checks your Folate level as this and B12 help your iron to function properly and to make red blood cells

Alesia profile image
Alesia in reply toclivealive

Thanks Clivealive I will and I am currently waiting for those results, last time they were checked my folate was very high at 923, not sure if this is due to B12d or the SIBO as apparently the bacteria produce excessive amounts of folate, ferritin was 69 but had dropped from 121 over 3 months for no apparent reason!

Retren profile image
Retren

I sometimes wonder what caliber of intelligence is being accepted into medical schools these days.it isn't,t just the misinformation but the lack of empathy re one reportedly cutting off a renewal prescription because the party seemingly owed money.when my father in law died and his safe was opened there were thousands of cheques he had never cashed going back many years it not only gave his patients the belief he had been paid but allowed them to keep their pride.my own spouse was a physician in the same tradition and on top of that a superb diagnostician.there should be more to treating patients than counting costs.I remember my own mother paying our GP with the items we traded when cash was low during WW2.and being grateful for the understanding shown.again a doctor who looked out for his patients How many of the current ones will be remembered for their caring?

Dewbuc profile image
Dewbuc

I absolutely agree with your comments. I was chatting with a pathology professor at the weekend. She was absolutely appalled at the stories about my care and the experience of so many others. She thought it truly disgraceful that many GPs were so ignorant regarding the very real dangers of B12 deficiency as well as the lack of care and frank rudeness of so many GPs.

Retren profile image
Retren

Dear Dubuc the new crop other than what seems to be a mere percentage seem to feel they are on an elevated level compared to those who have not qualified as physicians when they are in fact often abismally ignorant in regard to the basics of social interaction and should have taken courses in how to acquire that.Retren

Retren profile image
Retren

P sI also feel they often do not know anything beyond their chosen field of expertise this is of course a result of so much specialization.I find it distinctly off putting to be seated waiting for my doctor to finish gazing at his computer screen as though I have just landed from Mars it can,t be avoided I suppose but surely they should be able to remember individuals case history without resorting to what seems a singularly distant relationship.via technology.

Alesia profile image
Alesia

I think this is where the info comes from, this is from NICE guidelines.

Adverse effects

Adverse effects of vitamin B12 include nausea, headache, dizziness, fever, hot flushes, itching,

and injection-site reactions.

Cardiac arrhythmias secondary to hypokalaemia has been reported during the first few weeks of

treatment. The manufacturers advise that plasma potassium levels should be monitored for the first few weeks of use.

Rarely, acneiform and bulbous eruptions have been reported.

Very rarely, anaphylaxis has been reported.

No_fixed_abode profile image
No_fixed_abode in reply toAlesia

"Cardiac arrhythmias secondary to hypokalaemia has been reported during the first few weeks of

treatment" -- Thanks!

Think I had a session of arrhythmia this week after I injected, BP fell to 109/40 (usually 140+), heart rate was in the 70's (high for me, resting apx 60), IHR flashing on the BP monitor, massive palpitations, and I could feel my pulse was racing and slowing. I filled my lungs and pressured my chest and it seemed to calm and go away. This was one of the things I was worried about in self treating!

Now eating bananas (even though they really don't like me) and cured meats...

Bob

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