B12 deficiency- are my symptoms normal - Pernicious Anaemi...

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B12 deficiency- are my symptoms normal


I am currently having loading shots after being diagnosed with B12 deficiency, and just wondering if any of us following symptoms could be caused by this, and not just 'me' as I have thought for the last 3/4 years...

- restless legs/involuntary jerking, especially when tired.

- insomnia

- very slow brain response, cannot give a quick answer, often have to take 5 mins to think what I want to say. Always get my left and right mixed up!

- no menstruation for last 18 months

- constipation/bloating

- severe headaches, especially after any exercise

- poor blood circulation especially to feet and hands

I have many other symptoms too which I know are B12-related, but just wondering if anyone has any experience of the above?

Thank you!

11 Replies

yes, yes and yes

clivealiveForum Support

Has your Folatew level been checked Yellowkangaroo?

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


numbness and tingling in the feet and hands

muscle weakness


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 check with your doctor

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.

I am not a medically trained person but I've had Pernicious Anemia (a form of B12 deficiency) for more than 46 years.

I wish you well.

Thank you clivealive , my folate level is >20 ug/L (I have been taking 5mg folic acid daily for 10 months now due to epilepsy drug I am taking) but my ferritin level is low side of normal I believe at 32 ug/L - the doctor said these are both normal but I'm not sure? I have had unexplained mild anemia for a few years now but haven't been taking any iron supplements latterly. Basically I've had so many varying symptoms for a long time and tried to treat each separately, so still figuring out how much of it has actually been down to B12 or if I've just suddenly become deficient in it! Wondering if I ought to start taking iron supplements again? I have a follow up doctors appt in two weeks but would like to figure it out myself first so I will know if they are trying to fob me off

Have you also had your thyroid tested? I ask as my periods stopped when I had Graves’ disease (an autoimmune thyroid illness and as such, ‘related’ to PA).

Yes twice - the first time during tests relating to the period issue and it was on the low side of normal apparently but wasn't give the actual result... so had it checked again by my doctor 6wks later and was 3.3 mu/L [0.34-4.7] so maybe could still be an issue although doctor said it's fine...? From research underactive thyroid is what I thought the issue was until they discovered the B12 deficiency. Interesting that you have had periods stop too as doctor told me it couldn't be related 🤨

My thyroid was overactive (TSH <0.5 from memory) , I don’t know how being underactive (or possibly heading that way) affects periods I’m sorry.

Perhaps post on the thyroid group for advice? They may well suggest FreeT3 & T4 be tested if they haven’t already been.

By the time PA was diagnosed I was post menopausal so I don’t know if this would have affected things or not.

Regarding your iron and ferritin/iron stores, the optimum result is 80 to help absorb your b12. Folate should be high teens. Vitamin D needs to be 125+ but ideally 250 to support your thyroid. Did the surgery mention that you need potassium rich foods or drink with your injections?

I've had similar symptoms, went down the b12 route first and upped my cofactors of ferritin, folate and vitamin d but still was struggling. Wasn't until I had a full thyroid panel, I tested positive for TPO antibodies. My TSH was about the same as yours. I'm getting there but definitely think your symptoms are a mixture of b12 and thyroid. My periods also stopped so didn't complain about that but do wonder if it's all connected.

All the best.

Highland49 thanks for your reply, I was started on the injections without any appts with the doctor so really been going a bit blind and found out all I have by searching online! I will start taking iron straightaway along with the folic acid, and add in potassium rich foods - but think I will have to wait and see if my symptoms go away with B12 treatment before going further down the thyroid route as some have improved slightly already, having just finished the loading shots today. I'm in my mid20s so the periods stopping was a worry but the specialist found no cause, so I'm sure it's related to everything else. Thanks so much for your help, hopefully will be back to the energized and fun 'me' one day! All the best for you and your health too

Thanks Yellowkangaroo.

Just to mention that you need to know your iron and ferritin level before supplementing too much, only that too much iron can be harmful. Oh I see that you've replied to Clive about your level, that's good.

Really good that you're feeling slightly better already. If you've been ill for some time, it may take some time but onwards and upwards from now on!

Highland49 I thought you'd be interested to know that my periods came back just 2 weeks after the loading shots finished! 😁

Wow! And scary to know what an impact low b12 has on your body. Mine didn't return so rather relieved about that 😀

So good to know you're on the right track. I hope it all continues to go well.

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