Pernicious Anaemia Society
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Should I feel so awful after having B12 injections so recently?

I've been chronically tired for almost my entire adult life. I'm 27 now, and have suffered since around the age of 18. I thought for years it was just depression, or maybe my weight. Everybody around me was continually trying to motivate me to do more but I just physically couldn't, which led to a vicious cycle of feeling terrible about myself. In January, I finally went to my GP who tested my B12, Folate and Iron. I got a print out of the results but I don't really understand them. Apparently I'm low in all three, but my dr said it's nothing to worry about. She booked me in for 6 B12 injections and told me that I'd need injections every three months from now on, as well as giving me folic acid and iron tablets. After the initial 6 injections, I felt incredibly well. First time I'd actually had energy for years. But for the last couple of weeks, already I feel awful again. When I talked to the doctor last she gave me a print out about Vitamin B12 deficiency anemia and pernicious anemia. She said it would help me understand better, but I don't.

I feel so horrible again, and really, I can't live like this any more. I considered suicide in the past because I really did feel so useless, and I couldn't do anything. I feel pretty hopeless now, I'm crying all the time and I have no energy. I'm starting to wonder whether it's all psychosomatic, as my family have suggested.

I was wondering if anyone could help me interpret my results. I don't really understand whether I'm just deficient in B12, or I have pernicious anemia, or whether it's all in my head, really. I feel so confused, and my memory is extremely poor. If someone could help, I'd really appreciate it. I'm sorry for such an excessive post, I'm just so desperate, I feel like I'm losing my mind.

I don't know which figures to post, but I've seen these talked about, so:

Serum B12: 161ng/L (189-883.00 ng/L)

Serum Folate: 2.0ug/L (4.80 - 19.00 ug/L)

Serum Iron: 7.8 umol/L (7.00 -26.00 umol/L)

Serum Transferrin 3.83 g/L ( 2.00 - 3.60g/L)

Transferrin Saturation Index 8%

I don't know if any of these other results are important. I'm also not sure which of the figures I needed to post so I posted both. Thank you for your time.

11 Replies

Hi sorry you are feeling so awful but I am not at all surprised as your B12 and Folate are well below the bottom of the range and Iron at the bottom. This will be causing all your symptoms and it is NOT all in your mind.

I am pretty new to this myself so cannot offer a great deal of advice, but from what I have read on this forum some people have to have their B12 injections more often than the standard 3 months. How long has it been since your last injection?

My B12 and Folate were a lot higher than yours and I felt awful, I started self supplementing as I was still in range and this really helped.

There is a member on this forum who has a vast amount of knowledge so hopefully she will come along to offer more advice.

I just wanted to send this reply to give you a little bit of hope that things will get better as the folate and iron build up in your system, also if you feel you need the injection sooner than the 3 months ask your G.P.

Best wishes browny



Sorry you are feeling so low. Like browny said "no wonder with a low B12 and folate range" My B12 was 226 and I thought that was low !!

I was unable to tolerate the injections and only had 3. However my B12 did go over 800.

I then started to suppliment myself with B12 sublinguals { which I had to get on line }, and after a month my B12 shot up to over 2000. I have stopped taking them now and my B12 is still up.

I hope those on this site with more knowledge will get in touch with you. There is a site to could go on to it's called " b12d "

Dont give up, as it's not all in the mind, not with those results.

regards bowler


Could you please recommend the best brand of online sublingual?. your reply would be great helpful for me/others


I took Swanson's sublinguals, [ Methylcolbamin ] which I got from Amazon.


Thank you both for taking the time to reply and for the encouraging words. It really helps to know that I'm not the only one who has experienced this, and definitely gives me hope that I'm not completely losing my mind. Will try getting in with my GP this week. Thank you again.


The good thing about this forum is that you realise just how many other people are in a similar situation to yourself and that gives you confidence - you must not think for a second that it is all in your head.

The advice given above I would definitely validate. I am one of those people who have been granted high frequency injections as my symptoms return after a ridiculously short amount of time. However, it did take a fight with just about every medical practitioner that I met for an awfully long time! All of the tools that you need are available and, as someone above has said, the b12d site has what you need. The main thing is to access the information, understand the situation you are in as much as possible and then return to argue your case.

I downloaded things such as the protocol for treatment, the symptoms checklist etc. Then I tracked my symptoms against that list and got advice from the doctors available from that site. You have to hold your ground!

Good luck.


Hi :)

My initial b12 was 147 (over two years ago) it took a year of monitoring 6 b12 boosters and another year of monitoring for the docs to agree I did need the injections - highest b12 about 500 by the time they decided i need it back to 165. I had my proper booster set 6 weeks ago and am already tired anxious and down again! I wonder if people get their b12 checked after injections maybe each year to make sure if they are working or something else is causing the symptoms?

I would definitely say with your b12 and folate scores its not a surprise you feel rough. I know from experience. For me the biggest symptoms we memory/ fuzziness/ anxiety and feeling like my brain was failing me as well as ulcers and cold sores, For a little while I felt more positive and have not had ulcers since the injections.

I think you can be b12 deficient without having pernicious anaemia, depending on the cause. If you have intrinsic factor antibodies you have PA. I'm not sure how important it is to know the difference but could affect whether or not oral b12 supplements would help. Hopefully someone will be able to explain this better

Hope you feel better soon


I went to the Dr today and mentioned how I'm feeling. I asked if she could repeat blood tests, she said this would be "of no benefit to (me) at this time" and that I'll have to wait for my three month check. She said that my symptoms are not caused by the B12 deficiency as this would have been addressed with the intensive course of injections. She suggested maybe I have CFS instead, and instead gave me antidepressants. I cried through the entire appointment, but I stressed to her: I'm depressed BECAUSE I'm so exhausted, I'm not exhausted due to being depressed. She didn't really take it on board and booked me in with my regular doctor for two weeks time.

As you guys suggested, I had a look on the b12d site. Hopefully I can use some of the information there for when I see the doctor again. I realise now I'm going to have to really push to get this sorted, as mostly they're willing to chaulk everything up to mental health issues.

Thanks to all of you that replied. It genuinely, genuinely helps to know that I'm not out of my mind. Though it hurts me to hear that other people have had such a rough ride with getting treatment too, it does make me feel a bit more positive knowing that other people know what I'm going through.


Hi Invidia,

you are unwell, your doctor should treat you, if she does not think it is B12 related ( which from your blood tests it looks like it might be) then she has a duty of care to find out what is making you feel so ill.

Please book another appointment - perhaps with a different doc at the surgery and state you felt benefit from the injections but now feel really ill again, list symptoms and ask the doc what they think it oculd be, and how they are going to investigate this and wait.....

it sounds mad, but I have had lots of trouble with my GP's and this is the advice I was given - to state my facts and ask that specific question and believe me it did work - the doc was quiet for a bit, but I held my ground and said nothing , so they had to reply with what they were going to do next.

It may not lead to an instant cure, but it is a tool for communicting with docs that does put them in the position of resolving the situation.

You should have your IF antibodies tested - reason being that if you have intrinsic factor antibodies you can eat as much B12 as you like - you cannot absorb it from food - you will have to have the injections.

if you have any neurological symptoms your doc should refer you to a haematologist - it is your right to ask and they must not refuse.

best of luck



I hope you ended up getting the help you needed with more injections. This this is really hard when you can't get treated right.


You have had some great advice, and I just wanted to add your doctor is wrong. It makes me so angry that she's prescribing anti-Ds and labelling you with CFS when you've only just started your B12 treatment. It's ridiculous.

You can still feel awful for quite some time after the loading dose, in fact many people feel worse. It takes months to build up good levels of iron and folate, and your B12 injections wouldn't have been as beneficial to you because of this. B12 is a water soluble vitamin, it is absolute nonsense to believe that one jab 4 times a year is all you will need. Most of one jab is pee'd down the toilet within the first 8 hours of having it. One thing I would ask your doctor to check is your thyroid, this can be out of whack as well. Also vitamin D. And they should be testing you for anti-intrinsic factor and anti-parietal cells (the PA antibodies).

If you have any neurological symptoms, which most people do on diagnosis, the BNF allows for injections to continue every other day until no further improvement. Very few doctors follow this directive.

You will find lots of information here, including a full symptom list:

And there are a couple more support groups, the Pernicious Anaemia Society and a linked Facebook page:


And ask the members of your family to watch this documentary, they'll remove that psychosomatic label pretty quickly I'd wager:

H x


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