Feel Bad After B12 injection - Pernicious Anaemi...

Pernicious Anaemia Society

23,391 members16,494 posts

Feel Bad After B12 injection


Hey, So i had a B12 injection today at 11.30. As soon as i had this injection i felt little rush of dizziness. nothing major compared to the dizziness from being low in B12. my face automatically went a little red. (Nurse commented on this) and ever since i keep getting adrenaline like dumps in my body. Not a panic attack as don't get sweats, fast heart rate or anything. It basically feels like my brain dumps adrenaline and then 10 seconds later i'm fine. Spoken with Gp who said she has never heard of anyone reacting to it like this. My question is, is it normal to get this "anxiety," Increased tiredness and dizziness after an injection. Not sure if i want to go for the rest now.

Thank you :) xx

41 Replies

I've had 'reaction s'

See how you feel in a day or so.

Wrongly or rightly I felt at times it hit my system too quickly and I felt overwhelmed. Clivealive describes it like a radio suddenly picking up a signal too loud and clear.

At the beginning o certainly got alot worse before better.

Was your vel very low?

Are you having nasty symptoms from deficiency ?

Nackapan in reply to Nackapan

Level of b12 very low?

Thank you for your reply. My level was 210 which is not considered low at my gp. But I have numbness and pins and needles, dizziness, brain fog

The reason I asked as mine 106 and wondered if ' traction was been so low for so long probably body shocked.

You could still be feeling that though as serum b12 tests show all b12 so some not 'active'

Ask for a referral to a neurologist.

Wow yours was low. Have you had treatment? How do you feel? May I ask why a neurologist?

I'm 18m in.

Still having regular b12 injections.

Pins and needles and dizziness are neurological symptoms and should be checked out.

Ask your Gp.

Keep pressing on with your injection schedule. I felt a little worse before I started to get better. It really sounds like some type of anxiety if it happened that fast after the injection. I was scared to death of the first one but now I look forward to them because it gives me a mental rush because I know I will keep feeling better!!

Thanks for reply. It’s not the first time it has happened. I had injections last year and the doctor stopped them as they think I reacted to them. I had 6 “episodes” I’ll call them since my b12. It’s feels like the feeling u get when your scared.

Adrenaline rush? Maybe it is that from the thought is the injection?

Can low b12 cause these anxiety symptoms? And injections be making them worse or am I now dealing with anxiety? X

I’ve read on this forum that low B12 causes anxiety for some. Also that one form of B12 (methylcobalamin) causes anxiety for others. If you had your injection at a UK GP practice you will have been given a different form of B12, hydroxocobalamin, and I’ve not heard of this being linked to anxiety.

Nackapan in reply to JanD236

No I havent either.

I had anxiety as a symptom of b12 deficiency. That has now gone now with regular injections. Was new to me and was wondering what was going on.

The adrenaline rush I've also had. They nearly stopped mine at the start but I asked to continue.

I rarely get that rush now and If I do it passes.

So do carry on michellep1990 if you can to see if they help you.

So you go the adrenaline rush after the injections or before? I shall carry on give it a bit longer to see if it helps

The worse time wad my injection wad at 1530 and ad the b12 peaked in my suste it happened. Never before. I also can get hot flushes

Different from menopausal flushes I donr have.

It's only happened once recently when my head felt like a pressure cooker on speed if that Makds sense.

What was odd wad the injection did not hurt but wad deep . I think it not in so quickly . I thought it was a different make of Hydroxocobalamin. Even rang the pharmacist.

He thought it was what I've now been prescribed as different to what's usually use by te nurses. So I set injected expecting a reaction. Brave I thought butneedrd to know. Nothing. I have 3 sorts of Hydroxocobalamin. I'm told by fbirder they all so very similar in makeup.

So my conclusion is it's how symptomatic I am when i have it. How quickly it goes into my bloodstream. How low is my b12.

So man things .

My daughter goes to the surgery and had never had a 'reaction??

I can also get tinnitus badly after an injection. I used to call it the b12 buzz. This rarely happens now .

I've only once had the feeling of go go go. It lasted a day then I crashed??

Hope that helps

Initially I had constant headaches and injections brought on worse pain. Again rarely.

Nothing else has helped my symptoms and nothing else has been found wrong with me.

Nackapan in reply to Nackapan

Sorry vision down today

*peaked in my system

Both my daughter and I react exactly like that after an injection. We just call it the b12 wake up to minimise it. I don’t usually feel better until after 24-48 hours. But I have to be honest and say we’ve both slipped with keeping up our co factors and as b12 needs potassium that’s probably why!!!

michellep1990 in reply to Parksy

Thank you for your reply. How did you both deal with the adrenaline rushes? I feel like my anxiety got a lot more intense since taking the injections. Thought it may of gone this morning but it has not

Parksy in reply to michellep1990

Both my daughter and I found that the old adage Of fear breeds fear to be very true so we both got a wholefood (pharmaceutical vitamins are trash) multi b supplement, up the potassium and take magnesium L threonate and magnesium glycinate. Plus natural omega 3’s which all help anxiety and adrenalin rushes. We did used to do the adrenal cocktail which really helps but because in the U.K. you can’t just ask to her potassium levels tested we only do it when we need it.

michellep1990 in reply to Parksy

Oh ok I shall have a look into the information you mentioned. How long did your adrenaline rushes go on for after your loading doses may I ask?

Try eating banas regularly whilst you are on loading injections. They have plenty of potassium in them. I was told to do that when I started. Also you need to make sure your folate levels & other bs are all good as the vitamin bs work together.

Thanks for reply. I am eating 2 bananas a day it’s hard to get more food in as I’m really off my food at the moment. My folate was 8.3 which is considered normal x

Hi! According to my doctor you can create antibodies to the hydroxocobalamin which can cause a reaction (this happened to me, but is hard to test for).

He said a different type of b12 injection (I’m not sure of make up) might be better as the one I was prescribed was the generic one, there was another I could have but he’d have to apply for an exemption for it to be funded.

My last blood tests showed really high b12 so I’m not having the injections for 3 months and then checking again.

Sorry I know that’s vague as but I had similar symptoms to you (nausea, vertigo) the morning after an injection.

Thanks for reply. I shall speak with gp about it. Did you have bad anxiety after your injection? Well more anxious

Not anxiety but certainly the rushes of hotness / dizziness - definitely feels like a panic attack or like you’re going to pass out.

My doctor didn’t know how to test for the antibodies but for me the nausea etc was so bad it’s worth putting up with the fatigue for now

Yes that’s like mine. Massive rush in my body then goes it’s like it’s trying to get into a panic attack but does not get there. What b12 do you use

I’m in NZ - the front of the packet says Neo-B12 injection

Ingredients are listed as:

Hydroxocobalamin chloride 1.027 mg equivalent to hydroxocobalamin 1.0 mg

Sodium chloride 9.0 mg

Water for injections to 1ml

1 N acetic acid is used to adjust ph

Manufactured by Pfizer Australia

I hope that’s helpful!!

I had similar feelings of anxiety in the past after my injections and the nurse advised to make sure to be very well-hydrated the day of a scheduled injection. Also, I always drink a bottle of room temperature water (it absorbs better if room temp) within a few minutes of the injection. No more issues. Hope that will help you too!

Well, I can understand how it made you feel, and it is not nice to feel this way. I have never myself had those symptoms after an injection, but had them before it was due. I know you cannot have too much B12, as the body throws out what is not needed. I hope you can get it sorted out, but it is very stressful at the moment with this Covid 19 and I think we are all getting stressed over it. I do not think it was an overdose of B12, so try not to worry about that, but maybe other people might have an answer. Just wanted to let you know we are all here for each other. Briarhillcat

For the first 6 months I started receiving shots I definitely felt a "rush" almost immediately after getting my shot. My face would sometimes feel warm too. I thought everyone felt like that when they got a B12 shot. I kind of enjoyed the feeling because with it came a rush of energy. My husband would joke that I was having shots of amphetamine. I don't get that rush anymore. I guess things have healed and my body isn't reacting to it as much.

michellep1990 in reply to MoKayD

Thanks for your reply. I think we are talking about different rushes! My is an adrenaline rush not just when I have injection but also keeps happening every hour or so. It’s horrible and makes me panic! It’s like the start of a panic attack but not panic attack

MoKayD in reply to michellep1990

Can you feel your heart pounding kind of hard in your chest?

michellep1990 in reply to MoKayD

No I get palpitations but not same time as the adrenaline rush

MoKayD in reply to michellep1990

Oh, I'm sorry, that sounds awful. Hopefully your reaction will subside when your body heals some more. I can barely tell I've had a shot now unless I've waited too long to get it. I can tell I need a shot when the tip of my nose starts to feel cold. After I get my shot the tip of my nose feels tingly and warm

Do you know what form of B12 you are receiving? Some tolerate cyanocobalamin much better than the other two forms. Methylated vitamins in particular cause me major anxiety problems so I avoid them at all costs. I would also check your labs and see if you have a recent potassium level.

Thanks. I’m on the b12 injection that starts with h. Also my potassium was 8.3

No my potassium was 4

How often are you getting shots? Potassium (and folate) deplete pretty quickly if you’re receiving frequent injections. If you’re having injections often and that lab was taken a little while ago, it’s possible that could be the issue.

I would see if your dr would allow you to try the cyanocobalamin b12 injection. That’s pretty much all they use in the US and I know some people think the one you’re on is superior but cyano is very well tolerated. Yours may be very effective but if you feel awful on it, I don’t think it’s benefits outweigh the side effects you’re experiencing. I really hope you feel better soon. It’s awful to feel sick and worse when the treatment doesn’t help. 😔

I only had my first one yesterday! Due my next one Friday! My bloods were done 2 weeks ago. Would they lower that quick?

Oh no, they should be fine then. I was thinking maybe you were doing them every few days. I would ask about a different form and see if you tolerate that better. There is also a Facebook group called Pernicious Anaemia/B12 deficiency- support group and it may be helpful to you as well. Lots of people talking about their experiences with these same things.

Have you tried 'Nature provides' - 2400mcg Bioactive B12..pure and vegan...Contains:- dual coenzyme B12 Methylcobalamin +B12 Adenosylcobalamin?

Just wondered !?

Always come home and drink 330ml coconut water after injection, disgusting but has potassium and very refreshing as always feel thirsty had heart palpitations and nervous sweats prior to loading and for 3-6 months after treatment began

You may also like...