B12 Injection Side Effects - Anyone Else?

Hello, I was diagnosed with low B12 last year following routine blood tests to investigate chronic fatigue and was started on injections.

I started with the 6 loading doses every other day for two weeks but the GP stopped them by the third one due to side effects I was experienced - I was very poorly after the first one - I felt like I’d been hit by a truck and drugged with sleeping tablets and I was so unwell. The other 2 just made me nauseous and dizzy but the GP was concerned by how unwell they were making me so he stopped the loading doses and moved me to 12 weekly ones.

Since then, I’ve been doing pretty well and had no side effects, and although I’m still experiencing chronic fatigue the injections have definitely been helping.

However this last injection I had, I was really struggling with my chronic fatigue for about two weeks leading up to the injection, and although the injection made me feel much better, I was very dizzy and nauseous for 24 hours afterwards. So it got me wondering if the side effects were not because it was too much too quickly which was why the GP stopped the loading doses, but actually because it’s not enough? So just wondering if anyone else has experienced anything like this? Trying to educate myself and keen to learn as much as possible!

Thank you!

[Nackapan]

Mind were nearly stopped in the loading phase .The nurse was shocked by my reaction .

I asked for them to continue after finding this forum.

Indeed it's a rocky Road.

Depends how long you were defiant snd how low you got.

12 weekly sounds not enough .

Ask for 8 weekly and see how you go

[Hidden in reply to Nackapan]

So sorry to hear you reacted too. I’m unsure as to how long I was deficient for, I had symptoms of fatigue for about a year and brain fog after having Covid and then I had pins and needles in my hands for a few weeks on and off before I had my first loading dose. My B12 wasn’t awfully low, but it was below normal range and I know it is common to get symptoms even with a B12 in normal range as only a percentage of it is functional.

I will speak to my GP and ask about increasing my injection frequency and see if that helps - I didn’t know I could up it so that’s great news and I’ll definitely ask! Thank you.

[Nackapan in reply to Hidden]

NICE guidelines do say 2-3 monthly.2 monthly for neurological symptoms.

Pins and needles, headaches ect .

So should be able to up them for a trial easily.

Anything more g.ps usually want specialist input .

To cover their backs I think as no training beyond a serum blood test.

I've recently had another 'round ' to keep my 2 weekly b12 prescription.

I prefer the need recorded on my medical notes.

Also to get awareness put there for this group of G.ps which is big as covers 4 surgeries .

I'm not a rarity .

We are in s climate of audits showing 3 monthly b12 injections are enough to kerp symptoms away.

For some this is true .

Also nurses seem to think one are needed and trying to stop them nationwide.

Ignorance of need and B12

And workload .

Self injecting the 2ay forward lije diabetics have to.

I've been doing subcutaneous b12 injections at home with a prescription for 6 years now .

It's off licence.

I have an IM one at the surgery. Every 3rd one.

For most 3 monthly b12 isn't enough .

My mum needs 8 weekly

My daughter 10 weekly

I'm presently prescribed 2 weekly .

I buy it too .

Will not go without and back to a dark place .

[Hidden in reply to Nackapan]

Thank you. It’s so scary isn’t it the lack of knowledge and support around this, and not taken seriously enough. I’m glad to hear you and your family have found a good regime that works, I’ll definitely be asking my GP. When you say they would want specialist input - which specialist? Thank you.

[Nackapan in reply to Hidden]

They only seem to want this if more injections needed than 2 monthly.

My daughter however 10 weekly .

They wanted input from gastroenterology. She wax initially prescribed by them.

For me initially from neurology. As I'd seen many due to symptoms.

Lastly haematology.

I'd never seen.

Advice sought on safety .

My mum 8 weekly all prescribed from G.p .No specialist involved .

So very different .

[Hidden in reply to Nackapan]

Ah yeah sure, that makes sense. Thank you.

[Oneash]

Make sure you are getting co-factors. It makes a big difference to how effective your B12 is. But if you aren't getting enough B12, go easy on the folate. Vitamins B6 and B1, vitamin D, magnesium, zinc, and DHA omega 3 fatty acids from fish oil.

[helvella in reply to Oneash]

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[Technoid in reply to Oneash]

"and DHA omega 3 fatty acids from fish oil."

*cough* or EPA/DHA from algal oil. Which is where the fish get it from in the first place. While it's reasonable to not go overboard with folic acid, there is no reason to restrict dietary folate, even in B12 deficiency.

[Oneash in reply to Technoid]

I thought, from Martyn Hooper's book, that's how you get into the "folate trap" taking folate supplements, without enough B12 to balance?

[Technoid in reply to Oneash]

You can't "balance" the one-carbon cycle when there's not enough B12. Folate trap is unavoidable in severe B12 deficiency. Reducing folate intake won't allow you to escape folate trap, it just means even less folate will be available to the already dysfunctional cycle.

This is a decent desciption of what happens in folate trap:

firstclassmed.com/articles/...

[Oneash in reply to Technoid]

Thank you for this, very informative.

[Hockey_player]

I get my husband to give me an injection once per week because my symptoms come back in 3 weeks. They advise sticking to every other day until you are symptom-free. Then find a schedule that keeps all symptoms at bay. Everyone is different. Some people need it every day. Some people might be able to get by with once per 12 weeks. I think the math they did in computing that intervals was faulty. It was based on someone having a function re-uptake system. When the B12 is reabsorbed the process is the same one that is broken in those of us with PA.