Hi, I am having my third week of B12 loading doses (albeit with a weeks gap between them for various reasons). I had few side effects with the first two weeks worth (6 injections). However, I had the first injection of the last three yesterday and the side effects seemed very strong. Tingling all over, very anxious, slight nausea and upset stomach. These were worse overnight, where I had little sleep, and the sleep I did have came with vivid and anxious dreams. I felt like I had been poisoned! It is making me think I shouldn't have the other two, but after the first 6 injections I did still have slight pins and needles sensations in my feet and hands, so I feel like I should have the others. I have heard others mention side effects, and how they seem to be amplified at first from finally getting treated. I also understand that it is almost impossible to overdose on the stuff. However, I am a bit frightened by it now, and I'm not sure what to do for the best. Any advice welcome. Next injection is due tomorrow morning!
B12 loading dose side effects - how b... - Pernicious Anaemi...
B12 loading dose side effects - how bad can they get?
Hi natcap2 I'm sorry to read that you are having a "hard time" at present however it is not uncommon for some symptoms to appear to get worse before they get better as the B12 you are having injected starts repairing the damage done to your nervous system and your brain starts getting multiple messages from part of the body it had "forgotten about" or lost contact with.
I sometimes liken it to a badly tuned radio on which you have turned the volume up high trying to catch the programme you want when all of a sudden the signal comes in loud and clear and the blast nearly deafens you.
A lot will depend on the severity and longevity of your B12 deficiency as to how long before there is no further improvement or recovery.
Some symptoms will "disappear" quite quickly whereas others may take months or even years. There is no set timescale as we are all different.
It is also important that your Folate level is monitored as this is essential to process the B12.
There is a complex interaction between folic acid, vitamin B12 and iron. A deficiency of one may be "masked" by excess of another so the three must always be in balance.
Symptoms of a folate deficiency can include:
symptoms related to anaemia
reduced sense of taste
diarrhoea
numbness and tingling in the feet and hands
muscle weakness
depression
Folic acid works closely with vitamin B12 in making red blood cells and helps iron function properly in the body.
Initially, replacing B12 will lead to a huge increase in the production of blood cells and platelets (which occurs in the bone marrow) and can lead to rapid depletion of folate and iron stores; this can then limit the expected recovery of Haemoglobin.
Both iron and folate may be needed so please have these levels checked by your doctor.
I am not a medically trained person but I've had Pernicious Anaemia (a form of B12 deficiency) for more than 46 years.
I wish you well.
Thanks clivealive. I had my iron and folate levels checked before I started the B12 and they were fine. How long through the process of loading doses should it be re-checked? I think my GP suggested once all the loading doses were done.
I had read your post before likening this process to a badly tuned radio that then finds the signal. This certainly feels deafening. I was shocked to suddenly feel this bad. As long as having the B12 can't do any neurological damage, and just repair then I feel I can put up with it. I have panic disorder which may have something to do with having low B12 for a very long time. The B12 doses are certainly testing this.
Does anyone happen to know what the implications are for the off-spring of people with PA. I inherited this from my father. So my kids obviously have a 50:50 chance of inheriting it from me. If I have been low in B12 for as long as I suspect, I was low when I had my two kids. It can't have been that bad as they appear very healthy, but I am wondering whether their stores are also on the low side, which might then become a problem later on in life. I will talk to my GP about this at some point, but need to get myself sorted first.
I don't know know about the genetic ramifications of P.A. are other than it can be inherited whereas mine was due to gastric surgery at the age of 17.
As your iron and folate levels were OK at the start of your treatment your doctor appears to be "on the ball" with regard to re-testing as some supplementation may be necessary. Please remember that I'm not medically trained - he is.
I sometimes suggest keeping a list of your neurological symptoms and grading them day by day noting any improvements - or otherwise. This may come in handy if at the end of your loading doses you feel that there is still room for further improvement (as the guidelines state) and may need to have them continued. That is not saying that all symptoms have to have been "healed" but until they stop getting any better.
Some may take years as unfortunately, a severe deficiency may cause damage to brain and nerve cells that is very difficult to reverse and early detection can be critical in preventing permanent neurological damage.
This last paragraph is not meant to scare you but it is the "worst case scenario" if the deficiency is not treated effectively as the P in P.A. is rightly called pernicious...
You are now getting the right and effective treatment
I really do hope you start to feel better soon. There is life after P.A. and I'm still "clivealive" and 77 years old.
I have 36 hours of awful symptoms after my injections so I had one loading dose a week for six weeks. Now I'm self injecting I find I have no symptoms if I use a 500mcg dose rather than the 1mg.
Thanks for letting me know fionasloane. I postponed my last 2 loading doses as the last one really scared me, but starting again Friday as I do feel I need more to continue repairing. Am trying not to dread it!
Good luck! Let me know how it goes.
Hi again, I had the shot on Friday and that day I felt great! Didn’t feel so good yesterday, but nowhere near the reaction I had before. I am relieved and think spacing out the remaining loading doses weekly is a good way to go. It was good to hear your experience. Thanks.
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B12 loading dose Questions
