B12 loading doses feel terrible - Pernicious Anaemi...

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B12 loading doses feel terrible


Hi all,

I recently got diagnosed with a B12 deficiency. I am having neurological symptoms of neuropathy, vision fuzziness, brain fog, fatigue, and elevated anxiety and depression.

Folate level is normal and iron is borderline low. Doc prescribed an iron supplement and 6 loading doses. One shot every other day for 2 weeks. Today will be the 3rd of the loading doses. I feel better right after the loading dose but have generally been feeling terrible. I guess I just need some support and for someone to tell me that it's gonna be ok. I am so scared that these neurological symptoms will be permanent and the anxiety is taking over my life.

I literally could not stop crying yesterday. Likely, my deficiency is from being on metformin and birth control long term. I have been anemic before but have always taken a multi vitamin and iron supplements sporadically. Any tips or support would be appreciated, thanks much!

34 Replies

Hello, first of all I wanna say Hang in there! It does get a little rough when you start loading but I can tell you first hand as well as so many others on here that it does get better. I am 6 weeks now with every other day injections because I had neurologic symptoms. I have seen a definite improvement in all my symptoms. I know I still have a ways to go to see complete improvement but just try to be patient and calm. Stress increases the symptoms. I have found that out first hand. Focus on the small improvements as they come. Keep a journal of your improvement of symptoms so you can look at it and be reminded of your healing. It is gonna be a slow process, so as I heard someone else on here say... you need to be a patient patient. You will get better. I had alot of numbness and tingling and vision problems and headaches as far as neurological symptoms. All of them have improved significantly in only 6 weeks.

humaashraf in reply to shaylynn

Hi Shaylnn,

Thanks for responding. I am super nervous about having to advocate for myself post these loading doses. I just know that my deficiency has been happening for a while. I am hoping that my doctor knows enough about this deficiency to treat me according to my symptoms.

The doc wants to see me on the day of the last loading does to evaluate my symptoms and test for B12, liver enzymes, etc. I just know that I will need shots for a while. What kind of info should I arm myself with for my last appointment?

Your advice is greatly appreciated. It is so challenging to not stress about this since it feels like it is taking over my life.

shaylynn in reply to humaashraf

As far as arming yourself... I haven't really been in that situation, as I am in the US and my naturopath doctor has been great with giving me all the B12 medicine I ask for. I have based my treatment off my symptoms and not any numbers. She has agreed that is the best route. Maybe someone else more experienced with your situation on here can help with that aspect on how to arm yourself.

And I know it sounds crazy to say not to stress. I still stress somewhat every day to a degree but try to at least give it a shot and do whatever it takes, deep breathing, yoga, meditation or whatever else calms your nerves to get through this early phase. Best wishes to you!

humaashraf in reply to shaylynn

Hi Shaylnn,

I am seeing a regular doc, an internist. I hope I won't have to advocate too strongly for myself. These neurological symptoms are super scary. Maybe if I get resistance, I can look for a different doctor. Thanks!

fbirder in reply to humaashraf

Arm yourself with this NHS document... hey.nhs.uk/wp/wp-content/up...

You will see that it recommends lifelong treatment, with no further testing for B12 levels.

You should also be having injections every other day until there is no further improvement in your symptoms. Ask the doc to check the British National Formulary (they will have a copy, probably online). Here’s what it says for people, like you, with neurological symptoms...

Pernicious anaemia and other macrocytic anaemias with neurological involvement

By intramuscular injection

For Adult

Initially 1 mg once daily on alternate days until no further improvement, then 1 mg every 2 months.

humaashraf in reply to fbirder

Hi fbirder,

Thanks for your reply. Do you have any US guidelines as I am not in the UK? or if you could direct me towards where I can possibly find that info? Thanks much!

fbirder in reply to humaashraf

Frayed Knot.

It does seem a lot worse in the US then over here.

Gambit62Administrator in reply to humaashraf

This may be of help in the US


seems to draw a lot from the BCSH standards

humaashraf in reply to Gambit62

Thanks Gambit62. I will take this to my doctor. She wants to see me prior to my last loading dose to test levels again. I'm anxious of bruising her ego but there is absolutely no way I cannot advocate for myself, especially if I am having neurological issues.

shaylynn in reply to humaashraf

I am in the US too. I HIGHLY recommend seeing a naturopath doctor. They are way more willing to listen and be open minded about treatment. Mine is amazing and she pretty much lets me call the shots on how often I inject. She lets me decide based on MY symptoms and not a number.

Very Good points here x

Jessie8 in reply to humaashraf

Hi humaashraf,

Please try and not get stressed as Shaylynn is correct, it can intensify your symptoms.

I think it depends where you live as to what treatment you have ongoing.

I’m in UK and my dr would only give me 5 loading injections even though my neurological symptoms are still very much present. After my 5 loading injections,I felt much worse but this is normal.

I was also advised to take Magnesium, Folic Acid and Vit D.

If you finish with your loading injections and dr won’t give you any more and are still feeling crap, Join the pernicious anemia society and they will help tackle the dr’s for you.

Hope you start to feel better soon.

In the US, you will be prescribed monthly cyano-B12 injections. Your folate will get used up quickly after you start on injections so yo will need to start folic acid supplements.

You will want to ask for weekly cyano injections to support repair of neurological damage. Start a logbook of symptoms and measure the severity daily. Your own scale is fine. Provide this list to your GP and ask for it to be included in your record. Your GP needs to get comfortable with you monitoring your own symptoms.

humaashraf in reply to pvanderaa

Hi pvanderaa, thanks for this info. Considering how I feel the day after the shot, I think I may need something more frequent than weekly injections. But I will try to be patient and wait to see how I feel after the last loading dose.

humaashraf in reply to pvanderaa

I have started my symptom log book today, thanks for the tip!

pvanderaa in reply to humaashraf

Also record your food. I developed an intolerance for gluten and dairy (casein protein). Don’t know if my deficiency came first or if the deficiency was caused by these in my gut.

Are you vegetarian?

To also support nerve repair, you will need a daily multivitamin, vit B1 and vit B6. Nerve repair is very slow - months and years, so the logbook will help you monitor improvements.

You may heel worse at first. Some new symptoms, very similar to those caused by the deficiency, will shoe up after each injection. You may initially think that you are having a reaction or that the injections aren’t working.

Symptoms like pain and hunger are due to nerve repair and the brain’s interpretation of the stronger signals.

The pain is an illusion and you can convince your brain of this if you do gentle range of motion exercises. Getting started is the hardest but you will find that the pain goes away.

Stress and worry about the pain make it seem worse and last longer.

Hello For the last few months I have been super tired and super anxious. Loading doses don’t work overnight, I know the same as you that the deficiency has been happening for a while. I get neurological symptoms in my legs too. Have just started loading doses 10 days ago. Felt great after three days now feeling not so great but I have to trust what others say that I will get better. I remember someone saying “we didn’t get ill overnight so we won’t get well overnight” but I’m hoping it’s in terms of a month or two to get recovery rather than years. Please keep posting so I don’t feel so alone x

Hi Rugbyslammer,

Thanks for replying. I know everyone says it will take a while but feeling like this often is so hard. I'm scared that I will lose my fun, happy personality because of this. I'll keep posting my updates. I'm sorry you feel so alone but know that you aren't, we are in the same boat.

Just hang in there humaashraf. 9 months on I feel mostly well. Everyone is different and it's a complex disorder. I had all the things you mention some to a very bad level and felt my doctor must have thought I was mad. I thought I had to have had a brain tumour or MS but on reflection it was all PA related. Just keep going and through time you will slowly but surely see a difference, big hugs x I liked Shaulynn's reply too but for me, it took months for real progress to be seen, but it will happen. Wishing you well.

Hi Miss-guineapig, thanks for replying. It's just so nerve wracking that recovery will take such a long time. I've already been feeling pretty down and crappy for the last 2 months. I guess I should feel lucky that a doctor finally caught it, but right now all I feel is anger that no one caught this sooner and that I have to go thru all of this to just feel like myself. Have you been on b12 injections for 9 months? Or just supplementing yourself? Did you feel bad after loading doses as well?

I also had many scary symptoms that were worse after loading doses. I'm nearly 6 weeks post loding doses now. Anxiety has greatly reduced. S0 have the electric waves through head and body. Palpitations not as often. I'm left with severe fatigue and light sensitivity, vision down and some headaches. I'm due 1st maintenence injection on Monday as although I should have continued the gp was against it and I disn't have the confidence or energy to fight it. I was so much worse on the injections for 2 weeks. So I've this injection 6 weeks (earliest I could get by simply booking it with nurse) Then 8 weekly. So hang in there it does seem alot slower to repair than I dreamed but it is happening.

I went for a short walk tokay. Believe me that is progress after being virtually housebound apart from medical appointments since 1/10/18.

I wish you well. I used breathing exercises and aromatherapy oils for anxiety. It definitely makes symptoms worse . I was prescribed Amytriptyline but so far I've managed without. Good to have it on the shelf though! I take vit D vit c folic acid 400ug and zeaxanthin and Lutein for eye health. Then on alternate days multivitamin. I'm also trying an oral B12 spray to see me trough to injection.

I tested negative to intrinsic factor

Also hb 13 and haven't megoblastic aneamia. That's what the go used against me having more jabs. He says I've not pernicious anaemia. I don't know as a meat eater and foodie why else did my level drop to 106??

I wish you well. Try and stay calm through this email difficult times.

Oh and the vertigo and unsteady gait gone. Only wobbly at the end of the day 1700hrs. You see how important a journal is . Once gone almost forgotten!

Hang in there....this is NORMAL....i felt absolutely dreadful when on loading doses....it took a long time to get this ill, so it takes some time to get better.....the body is just firing up, using all that B12 and kicking starting loads of processes. I had terrible neuro/psychiatric symptoms, loss of leg function, pins and needles, horrific 24/7 anxiety and panic attacks, dreadful dizziness, deep dark moods and a host of other symptoms which began lifting after two weeks of daily injections (i self inject). Look at this difficult time as part of the healing process....that easier said than done, but you are on the road to recovery. Sometimes it is one step forward and two back but with time it will even out. xx. J in Ireland.

Hi jarlethblue, thanks for replying. How did you decide to self inject after loading doses? I'm so scared that I'll have to fight with the doctor to get more maintenance after loading doses. I just don't know if I'll have the energy to. I just made an appointment with a neurologist. I will see her the day before my last loading dose so I can go to my pcp with neurology recommendations. The deep, dark moods are so terrible, it's hard to pull myself out. I've been staying with my family this week but I'm scared of how I'll feel when I head back to my apt, dreading feeling alone.

you will be ok......try and remember that it is the illness that is causing these low moods....it could also be that you are low in potassium which is used up when the B12 starts making new cells so drink lots of coconut water and eat bananas and other potassium rich foods.....i found that my mood was very bleak when on loading doses but could be lifted with potassium and also to smile a lot as it can help fool your brain that all is good......i knew i could not survive on three monthly shots so got supplies and began self injecting a month ago....i am now doing it everyday to try and keep on top of my symptoms....because my last blood test showed my b12 blood level at over 2,000 there is no more help from my doctor - but the level in the blood is no marker for how you feel....it is the amount that gets into your cells and so i will continue to do daily injections. I really think after your loading doses you should give serious consideration to taking matters into your own hands and self injecting....it is a simple process and lots of advice here on how to do it and where to get supplies. You are then in control of your healing journey which might take some time, but you will see improvements happen. x. J

ps...you are NOT ALONE....YOU HAVE US ALL HERE TO TURN TO.....this is a dreadfully lonely illness, but this forum is a life line....USE IT. XX

Nackapan in reply to jarlethblue

Sorry realise that message was to humaashraf

Nackapan in reply to jarlethblue


For me, methylcobalamin injections worked far better for my neurologic symptoms. The cyanocobalamin makes me feel terrible. I don't know why that is.

Do you feel any better 3 months on? I have just started my B12 injections I have just had my 4th after the doctor tested me and said I had a low level of 110. I must say I feel awful. Reading this has helped as I honestly feel there is a lot wrong with me. I suffer from internal shaking and weakness, racing heart and sometimes heart palpitations, problems with my vision where it shakes when I look at certain things, dizziness, head pressure I have had now for over a week it seems and I’m sure I have anxiety about it all now too. Plus the injections have given me diarrhoea and do feel sick at times.

Any advise would be great if people had any of these symptoms and what I should tell the doctor to do next? I’m due to have my final injection next week and then that’s it they have said for a few months until I have another blood test!

We are away at the moment and I have felt awful, rushing around doesent help I’m sure and even finding hard to sleep now with heart racing and head pressure.

Getting me down now :(

Thanks Steph. UK

sbadd in reply to Jurassic2906

Im 10 weeks on after loading injections i had 6, i had everything you have my head pressure passed but i ended up having ct scan as was so scared something else was wrong, it only stopped a few weeks ago but now im suffering tachy heart and still bouts of heaviness in legs and arms, scared to have any more injections

Jurassic2906 in reply to sbadd

Has your vision got any better too? I don’t know about you but even when I try and go to sleep and close my eyes it’s like your head just feels shaky.

Your ct scan all ok?

I know how you feel makes you feel so bad you think there is more stuff wrong with you.

Have you been back to the doctors? Some people are saying that it takes ages for symptoms to get better but I think they only do with more injections? Anyone confirm thanks Steph

sbadd in reply to Jurassic2906

Ct was fine all other side effects have passed apart from tachy that comes and goes, odd muscle twitch and fatigue that comes and goes

That’s good I’m glad for you. Did it take a while for it all to pass then? Feeling like this for weeks is a hard thought. Want the head pressure and vision to get better. Have tinnitus too.

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