Feeling worse after b12 injections - Pernicious Anaemi...

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Feeling worse after b12 injections


Hi there,just looking for some answers as I'm new here and new to the world of b12 deficiency,lucky as I am I also have vit d deficiency too so I'm still getting to grips with all of this! This site seems like a gold mine of info so here goes...Docs told me ten years ago and after any subsequent bloods that I have "large red blood cells" but always told not to worry its "simply the way I am" recently went to the doc with the feeling I was a hypochondriac....tiredness,apathy,poor concentration,poor memory,feeling hungover etc,all things that I have now realised I had got used to and had been putting down to being lazy,getting older(47!) etc and really wishing I had gone sooner now! I'm having injections(hydrox) every two days for six jabs then apparently it will be hopefully 3 monthly unless I need them more frequently. The nurse seems to think its unusual to feel worse after an injection but I've now had 3 and the last one totally floored me,could barely move yesterday,slept nearly all day afterwards and the sighing and aching everywhere was terrible! Also noticed areas of skin which look completely normal yet feel like I have sunburn...randomly! Having fourth jab tomorrow and dreading how I'll feel afterwards as yesterday's was the worst so far and I've not got over that one yet! I'm also taking folic acid supplements from the doc and vit d supplements too.....really interested to hear from anyone who has experienced similar and can maybe help by telling me there's light at the end of the tunnel... Thanks all

32 Replies

Unfortunately some people do feel worse before they feel better - have been a few over the last few months.

Do you know if you have a sensitivity to cobalt? though I think if it was that your reaction would probably have been a lot worse.

The sunburn sensation may be down to the effect of B12 on your nervous system - signals that weren't getting through before are getting through now but it can take a while for the brain to adjust to the signal levels. Like me you can probably remember the days before digital radios when you had to tune in but if the signal was poor you had to turn the sound up really loud to hear what was happening and then suddenly the signal got stronger and it was like being shouted at and could be quite painful if the signal got really stronger - think its a bit like that.

Its also possible that the other symptoms could be your immune system starting to kick back in after a while of not really doing a lot as a lot of the symptoms we associated with being unwell - which can include feeling sleepy - are actually down to the body going into 'fight the infection' mode.

It will probably improve after the loading shots but you may find that it starts to kick off again when you have your first maintenance shot.

From your list of symptoms it sounds like you may have some neuro symptoms in which case the standard treatment per BCSH guidelines is actually injections 3xper week until symptoms stop improving (though sounds like that might not be the way to go for you :) ) followed by maintenacne shots every 2 months rather than 3 - though even that isn't enough to keep some people healthy.

Really hope you can manage to persevere and things do start to improve. Have you noticed improvements in any of the symptoms that you have.


Might be worth going through this checklist and identifying everything that seems relevant and think about what is going on with all of those symptoms, focus on the ones that are improving as the other ones should improve with time as well, though it can take a while for all of the damage done in the years you have been deficient to reverse.

Know I had aches and pains that I hadn't had for years whilst I was getting better as nerves woke up ... and a right doozy of a cold - first time I'd had the whole runny nose and violent sneezing that I hadn't had for years - because my body hadn't really had the oomph to fight infections properly

Auntyp62 in reply to Gambit62

This is me, I could have written this myself!

Foxy07 in reply to Auntyp62

Thank you for helping me feel almost normal rather than a complete fraud, most days I walk round with a hangover from hell without even touching a drink. On the odd occasion I do have a few drinks, sadly these days I get drunk easily so 2 G&Ts and I’m almost gone 🥴, I feel no worse the next day.

It’s unbelievable that there are so many of us out there barely existing & grieving for the lives we are no longer able to live & yet so little is being done for us.

Thank you all for taking the time to write your comments, believe me they all make a difference to so many of us for so many reasons.


Hi Janee635,

There definitely is light at the end of the tunnel. Last year with a reading of 120 for B12 and 35 for Vit D, after 6 injections I slept up to 15 hours a day.

2 weeks later I changed completely. I got my life back and now SI and take different types of B12.

Never again will I live like I did when my GP put all my symptoms down to my underactive Thyroid that I have for over 30 years.

Take control of your own health J

J 😊

Auntyp62 in reply to Jose651

This is me! I could have written this myself !

Jwindsor in reply to Auntyp62

Mee To....Take con trol...x

sirlam in reply to Jose651

Hi Jose651. Can I ask you about the different B12 you take? I am using hydroxo, just because I started on that! What are the advantages of the alternate forms in your opinion? Thank you!

Jose651 in reply to sirlam

Hi sirlam,

No bother at all, I SI HCobalmin and MCobalamin and take Andosylcobalamin sublingual. I also take Thorne B Complex that has all the other B Vits and Methylfolate.

Are you self medicating with HCobalamin injections S. They work very well for a lot of people, as does HC sublinguals.

As you know everyone is different, but I will try anything to regain my health to where it was a few years ago.

I was misdiagnosed in 2014 and in that year I lost a relationship with a lovely partner of 4 years. I didn't even like myself. I had changed so much. Isolation became my friend.

I promise myself I will never ever allow the medical professionals to pull the wool over my eyes again.

Sorry for the rant S. Try them all and see what makes you feel better. Look at Gambits posts for good guidance.



sirlam in reply to Jose651

Thank you. That is what I will do! I do sympathise - B12D does turn us all into loners - being with people is just too much like hard work when you are feeling so very tired.

Keep up the good work and I am sure your future will be brighter. X

Jose651 in reply to sirlam

Thanks S,

J x

Foxy07 in reply to Jose651

How and why can this happen to so many of us, my Doctor recently blurted out how sorry she was that they had got it wrong for so very long!!!!

This was shortly after being diagnosed as a 50 year old with osteoporosis, blooming amazing as I had been told 20 months earlier I had excellent bone strength.

After rejecting further treatment a month a go after being sick for over a month after trying Alendronate acid, my Doc took me seriously when I suggested they were all missing the problem that was staring them in the face, I’m not I’ll i told her I am just a little neglected! I have a really healthy diet eating at least 8 a day including pulses& lentils, yet I still look & feel like death.

The penny dropped & I was offered B12 loading shots.

I had my final one yesterday & sadly I have to admit the last 2 completed floored me, it’s all I can do to string a sentence together.

All I want is a little more help & understanding.


Are you on cofactors? Bcomplex 50mg/ folic acid 5mg. Make sure you eat alot of foods rich in potassium because your potassium can drop on injections (ive had it happen). I drop tons of coconut water to help that not happen. (Intake 6000mg a day). I also supplement magnesium daily as well. I'm sorry you feel worse :(

Foxy07 in reply to Ithinkimdying

Really helpful advice I will try this 👍

It took me 6 months of injecting once a fortnight, or more often, before I stopped feeling really 'down' for a day after my jab. So it can take a while (although most people seem to stop it after a much shorter time).

You'll want to take some other supplements - a B complex tablet with 100% RDA, multi-mineral tablet and maybe some Vitamin D.

clivealiveForum Support

Janee635 It's not unusual for some symptoms to feel "worse" before they get better after your B12 injections. It's not an overnight cure or pick me up as your body needs to heal the damage caused by the deficiency.

B12 can only be got naturally from eating red meats, fish, poultry, eggs & dairy products.

Your diet needs to include Folate (B9). Dark green vegetables like broccoli and spinach and dried legumes such as chickpeas, beans and lentils are naturally good sources of folate. Folic acid can also be found added to some cereals.

B12 and Folate work hand in hand.

I hope you start to feel better soon.

I had an immediate effect after the first injection, especially with the clarity in my eyes but it did not last long and after the 3rd or 4 th I felt awful. The same happened after my first maintenance dose but now coming up to my 4 maintenance dose the improvement is amazing. We all want an instant fix. Remember it took a long time to get to where you are and it will take a while to repair some if not all of the damage that your body has. Look to the future and being a new woman, because I know I am.

Must add that low vitamin d also sucks and now mine is better as well.

Nathan12345 in reply to Auntyp62

Auntyp62, Just out of curiosity are you fully healed now or do you still have some symptoms?

Auntyp62 in reply to Nathan12345

Hi Nathan 12345, I don't think anyone is fully healed but I no longer sleep all day and night. Most symptoms are greatly improved except for the tinnitus and occasional dizziness which I have had for years but maybe I am blaming it on b12 and that is not the cause..........for me life is the best it's been for about 5 years

Nathan12345 in reply to Auntyp62

Ahh i see, I've heard stories where people have been healed and some where people don't really notice it anymore, if treatment gets rid of my psychosis and blurred vision it wouldn't bother me as much it's great you're feeling better though

I know I'm late to the discussion (just started B12 shots a month ago), but a 2 1/2 years ago I started thyroid meds and my tinnitus (pulsing, not ringing) cleared up completely. The pulsing came back after my 2nd every-two-weeks (initially) injection, and I had an occurrence every day, even upon waking. I have my 3rd injection tomorrow, and so far today at 11a.m. I haven't had any pulsing. After 2 shots I can't say I feel any better, but not worse except for the pulsing which I was free of for 2+ blessed years!, either. Just was expecting something very different, fairly quickly. And I certainly hope the pulsing goes away again.

Yep I get that occasionally, I think it’s all part of having thyroid b12 issues. Remember it took a long time to cause damage and it won’t suddenly heal everything with a couple of injections. I remember getting more energy then gradually feeling better over a couple of months. I can now tune out of the pulsing as I am so used to it so not quite so annoying. Don’t forget to keep an eye on your folate as it often drops when the b12 rises, I take a b supplement that included folate to keep mine balanced.

Foxy07 in reply to Auntyp62

Would you mind if I ask how you got your levels to stay as they should?

Were you screened for celiac etc?

I am also supper low in vit D & B12 & recently diagnosed with osteoporosis, major panic on by the NHS thinking they have missed diagnosed me yet again!

Auntyp62 in reply to Foxy07

I took responsibility for my health and now by pass the nhs. I have a private blood test every 6 months and adjust my supplements as necessary. I don’t have P.A. but b12 and bit d drop easily and after a few months I found that injections were not enough so I take b12 sublingually.

Was screened for celiac but negative

I had exactly the same feeling first 3 injections even fourth but 5th and 6th injection. Wow...big change for the better.then a month down the line more energy.weight loss. Feeling good. Good luck hang in there.xx

I am on my 6 th b12 injection I get them twice a week for one month then it will go to once a week for one month. I also have to take folic acid 1mg three times a day. I had one amazing day an that was it. My dr said I should not be getting bad headaches an nausea after the the injection. I dont want to feel like this anymore. I was not this sick before all this crap going into my body.

I also have chronic anemia

hi all id just like to add my story. iv had lots of the symptoms for a long time but mostly over the last 5months its got worse, 2months ago i went to drs with a really bad headache i have had for 3moths it was like my head with stuffed with cotton wool and a pressure sort of feeling that only went away with laying down. they just said it was my anxiety which i have had all my life and then 6weeks ago and i found myself haveing loads of panic attacks i actually ended up in a and e cos i was that scared about what was happening .by the way im a big worrier and always think there is something wrong with me they said it was anxiety again and they gave me beta blockers which did help a lot for the palpitations and hearing my pulse in my ear.so after that i was just waiting for it all to go away. not wanting to go out not wanting to talk to anyone couldn't even be bothered to txt anyone back and just felt sad all the time really sad and worried. then 2weeks ago my dr said lets try a blood test as you might be b12 deficient so they took the blood and from that day i thought id take b12 pills from the supermarket just in case. and i felt 10times better after that first day, however, I got a bad cold that same day too nose was running so much and sneezing a lot. but even tho i felt like crap it still felt better then it did so i didn't care. then the results came in 3days ago and i was 120 and they said i should be 500. they put me on cyanocobalamin tablets 50mcg 3times a day for 3months. they say i didn't need the injection type as i have the ability to absorb them this way whatever that means. i was just wondering if this rings true with anyone else? also, i do feel a bit better but still feel very sleepy and dizzy now and then but it is not dizzy its a different feeling that i can't explain. do they take a while to work? should i start to feel worse before i get better ? and was that cold-related? thanks for reading if you managed to get to the end lol :) ps because I have anxiety anyway its hard to know what's real or not with me as i and everyone else had but the way i am as been anxiety. maby iv not had anxiety and it was this all along in disguise

I hope things have improved for you

Wow thank goodness I thought I was going mad, I felt fantastic after my first 3 injections and then went down hill rapidly. I had my last jab yesterday and feel like I have a hangover from hell today, such bad fatigue it’s all I can do to walk.

I spoke to the nurse yesterday and she said they have only recently started offering these jabs so she hasn’t had any negative feedback.

Maybe it’s simply because are levels are just so low and when they get boosted we feel worse than how we did at the start.

Can I ask, hope you don’t mind but have you had a Dexter scan of your hips & back..

Good luck fingers crossed we can both get some real help through this.


Unfortunately, some people might get happy with the results of B12 MIC Oral Injections. I personally started taking Super MIC B12 when my vitamin b12 levels were low. I purchased this Lipotropic Liquid Supplement which is made up of natural ingredients like Choline.

Inositol, Methionine, L-Carnitine and Vitamin b12 and doesn't feel any side effects even taking it for 6 months. I think you have purchased the wrong brand of b12 injections. If you want to treat vitamin b12 deficiency buy Super MIC B12 bottle from the store buymicb12.com/ and read B12 Lipo Shots reviews to know more about its benefits and results.

Hi. Thank you for asking! I am coping well enough and maintaining my B12 levels by 3 jabs per week. Any time I spread the jabs out, back comes the neuropathy. I am mixing the B12 types, taking both hydroxycobalamin and cyanocobalamin. How about you? I do hope you have kept yourself well and safe during these weird times! Best wishes, Sally

How are you feeling now? What you have wrote sounds just like me now x

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