Had a diagnosis of pernicious anemia three weeks ago out of the blue. Had first B12 injection on Monday and was given flu jab at the same time. Didn’t feel great after and couldn’t sleep - awake til 5 am. Felt rubbish on Tuesday but put it down to the flu jab and lack of sleep. Had 2nd B12 yesterday and experienced an almost total shut down while doing daily chores about three hours later, barley able to walk or breathe and no strength in arms. . Have dreadful pains and sensations in hands, arms and shoulders plus banging headache and couldn’t sleep again last night. Spoke to a GP and agreed to postpone further jabs until we know what’s going on. Feel so overwhelmed, frightened and confused.
Any reassurance or advice or insights would be welcome. Thank you
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I'm sorry to read that you had a difficult experience.
It's quite common on this forum for people to report that their symptoms get worse for a while before starting to get better.
My neurological symptoms increased eg lots more tingling and pins and needles for a while when I started treatment.
Allergy
It's very rare but a few people get allergic reactions to B12 injections.
Did you get any signs of an allergic reaction?
I would expect your GP to refer you to an allergy specialist if they suspect an allergy.
Potassium
I wonder if the GP has checked your potassium levels.
Some people can experience a drop in potassium levels (Hypokalaemia) when they first start B12 treatment. Maybe you could ask your GP to check your potassium levels?
Have you also got results for folate, iron and Vitamin D?
Forum members often report deficiencies in these as well as B12.
Some links I post may have details that could be upsetting. I'm not medically trained.
Other B12 info
Link about "What to do next" if B12 deficiency suspected or recently diagnosed
Try to track down a copy of the local B12 deficiency guidelines for your ICB (Integrated Care Board) or Health Board.
If you can't find them online, you could submit a FOI (Freedom of Information) request to ICB or Health Board website asking for a copy of or link to the local B12 deficiency guidelines.
Two useful B12 books
"What You Need to Know About Pernicious Anaemia and B12 Deficiency" by Martyn Hooper
Martyn Hooper is the chair of PAS (Pernicious Anaemia Society).
UK BNF treatment info is out of date. See BNF hydroxocobalamin link.
"Could it Be B12?: An Epidemic of Misdiagnoses" by Sally Pacholok and JJ. Stuart (US authors)
Very comprehensive with lots of case studies.
B12 deficiency is not always as well understood by health professionals as it should be.
Misconceptions about a B12 deficiency
(From Dutch B12 website - units, ref ranges, treatment patterns may vary from UK)
thank you so much for taking the time to explain this. Just knowing why I felt so bad is a big help as I was given no information about the jab or what could happen. Thank you again.
Sleepybunny I was also prescribed Vit D tablets which I am taking with yoghurt two days on and two days off to avoid stomach cramps and diorrhea. I assume folate are iron levels ok but will ask Monday and also for my full test results. I am booked in for an Intrinsic Factor blood test next Friday but think I may postpone in favour of more B12 injections on a weekly basis.
I am also going to ask to be referred to a consultant because this has been building for some time based on what I now know to be symptoms. Do you know what type of consultant should I be expected to be referred to? Thank you so much again.
In relation to B12 deficiency, I looked particularly at B12, folate, ferritin and other iron tests and full blood count (FBC).
There can be useful clues on FBC tests as to whether B12, folate or iron deficiencies are possibilities.
Low B12 can lead to enlarged red blood cells (RBC), this is called macrocytosis.
Low folate can also lead to enlarged red blood cells.
Low iron can lead to smaller red blood cells, this is called microcytosis.
A person with B12 deficiency (and/or folate defic) with iron deficiency, may appear to have normal sized red blood cells on Full Blood Count as the effects of the iron deficiency can mask the effects of the B12 (and/or folate) deficiency.
Doctors often look for signs of macrocytosis when considering B12 deficiency.
Some of them don't know that about half of people with B12 deficiency don't have macrocytosis.
Some of the links below are aimed at health professionals.
"I am booked in for an Intrinsic Factor blood test next Friday but think I may postpone in favour of more B12 injections on a weekly basis."
You and your GP may want to bear in mind that the Intrinsic Factor Antibody test can give a false positive result if blood is tested close to a B12 injection.
I have read that some labs leave at least 48 hours after a B12 injection before testing IFA and some say leave up to two weeks.
See section on Anti-intrinsic Factor Antibody Test in PAS link below which explains about false positive results.
Anti-intrinsic factor antibody test is another name for Intrinsic factor antibody test (IFA/IFAb)
If you get a negative result in IFA test that does not rule out PA (Pernicious Anaemia).
It's possible to have Antibody Negative PA but unfortunately some GPs may not be aware of Antibody Negative PA and may assume that a negative result in IFAtest means the patient does not have PA.
Diagnostic flowchart from BSH Cobalamin and Folate Guidelines which mentions Antibody Negative PA.
I believe Martyn Hooper who founded PAS (Pernicious Anaemia Society) tested negative several times before getting a positive test result.
"I am also going to ask to be referred to a consultant"
Referrals are expensive for GP surgeries so they may be reluctant. You may find you need to really push for referrals.
I used to write a short polite letter to GP requesting a referral and I included evidence that supported the request eg symptoms list, quotes from UK health documents etc.
These links may be useful
NICE when to refer B12 deficient patient to neurologist/haematologist/gastro -enterologist
If GP is reluctant to refer you, you could try asking GP to write a local neurologist or haematologist asking for advice on how to treat you.
Be aware that seeing or having contact with a specialist doctor is no guarantee of better treatment. There is a lot of ignorance about B12 deficiency among some health professionals.
Diet
Has the GP talked to you about your diet?
Do you eat B12 rich foods eg meat, fish, eggs, dairy, foods fortified with B12?
Excess alcohol can also affect B12 levels.
Has GP considered other possible causes for your B12 deficiency besides PA?
Have you been tested for coeliac disease?
Guidelines below suggest anyone with unexplained B12, folate or iron deficiency should be tested for coeliac.
Hi Sleepbunny and everyone else who has taken the time to offer reassurance and suggestions I am feeling much calmer now. I have joined the PAS as I know this is a lifelong issue now.
Sleepbunny, got my results of bloods pre 2 x loading doses.
Vit B12 106, (under lower)
Vit D 35, (under lower)
folate 4.4,
ferritin 90,
Liver function 24, (over upper)
potassium 4.2,
RBC 4.84,
white blood cell 5.3,
Neutrophil 2.92
my bloods 4 weeks earlier which sparked the B12 check were
B12 not tested
D not tested
Folate not tested
Ferritin not tested
Liver function 18
Potassium 4.3
RBC 4.52
White blood cell 3.88 (under min)
Neutrophil 1.88 (under min)
I have been referred to a Haematologist and GP is reluctant to continue B12 until after consultation. Appointment on 18 November.
I am anticipating that after 2 B12 loading doses my B12 must be higher than 106 now. I am booked in for an Intrinsic factor blood test this Friday but I know that irrespective of the results I have PA as I am not a vegetarian and I eat a healthy diet which luckily is high in potassium and folate and iron.
I am feeling better than I did this time last week before my first B12 I am no longer yawing all the time although my hands and arms are still tingly.
So I think my potassium, ferritin and folate levels are ok.
Your B12 result looks really low ... was it 106 ng/L or 106 pmol/L?
Do you have the units and reference ranges to go with the results?
It can make it easier for people to understand what is going on.
"that irrespective of the results I have PA"
There are other gut issues that can lead to B12 deficiency besides PA.
These include coeliac disease, H pylori infection, internal parasites such as fish tapeworm, damage to the terminal ileum (part of gut where B12 is absorbed), Crohn's disease and others.
I would expect your GP to at least test you for PA and Coeliac and to refer you to a gastro enterologist if you have gut symptoms.
Folate at 4.4 looks like it's probably in range but not by much (useful to have units and ref range)
A typical folate range in UK would be >4 ng/ml which means above 4ng per ml.
Have you asked your GP if you'd benefit from taking a folate supplement?
Just as with B12 deficiency, it's possible to have symptoms of folate deficiency with a result that is within range.
May also be worth asking your local pharmacist.
When people start B12 treatment, there can be an increase in production of red blood cells and this process needs other nutrients besides B12. Folate and iron are two I think are also needed.
I'm glad that you have been referred to a haematologist and hope you have a useful consultation.
I suggest reading about B12 deficiency prior to seeing haematologist and maybe talking to PAS.
Some forum members have reported unhelpful appointments/contact with haematologists so I suggest doing some B12 homework just in case the specialist has not done theirs.
Thank you again and I am reading and researching as best I can despite a cracking headache so limited concentration and feeling very tired. I have taken time off work to focus on my homework.
Apologies for lack of detail on my part I didn’t appreciate that there were different units. Results of bloods with units:
pre 2 x loading doses.
Vit B12 106 ng/L, (under lower)
Vit D 35 nmol/l, (under lower)
folate 4.4 ug/l,
ferritin 90 ug/L,
Liver function 24 umol/L, (over upper)
potassium 4.2 mail/L,
RBC 4.84 10*12/L,
white blood cell 5.3 10*9/L
Neutrophil 2.92 10*9/L
my bloods 4 weeks earlier which sparked the B12 check were
B12 not tested
D not tested
Folate not tested
Ferritin not tested
Liver function 18 umol/L
Potassium 4.3 mmol/L
RBC 4.52 10*12/L
White blood cell 3.88 (under min) 10*12/L
Neutrophil 1.88 (under min) 10*9/L
Thank you again. So grateful for your time and advice.
I remember how hard it was to do some research and concentrate with a head that felt full of cotton wool.
With a headache, maybe you need to take some rest.
My B12 deficiency triggered chronic migraine and I would hate that to happen to someone else.
Maybe read in short blocks of time when you feel better and jot down a few questions to ask the haematologist.
I really hope you have a kind, caring haematologist.
With a B12 result of 106 ng/L I'm surprised you're still walking.
I can see that your white blood cells and neutrophils ( a type of white blood cell) were below range.
Cytopenia is the medical term for when a person has lower numbers of blood cells than normal. For example, neutropenia is the term for when a person has lower than normal numbers of neutrophils.
Both B12 deficiency and folate deficiency can lead to cytopenia.
Liver function 24 umol/L, (over upper)
Might be helpful to find out which liver tests you had done eg
Alkaline Phosphatase (ALP)
y-Glutamyltransferase (GGT)
Bilirubin
Albumin
What has your GP said about your liver function result being over the upper limit?
I would expect your GP to repeat the same test within a few weeks and possibly order further investigations.
If you post any other blood test results, it's really helpful to have the reference range. Usually this would be in brackets, next to actual results.
Links to forum threads where I left detailed replies with lots of B12 deficiency info eg causes and symptoms, more UK B12 documents, B12 books, B12 websites and B12 articles and a few hints on dealing with unhelpful GPs.
Some links may have details that could be upsetting.
Sounds quite familiar. I was barely able to walk after my first jab, it took me 20 mins to walk a journey to the shops (inching along like a 95 year old) that would have taken me only 4 mins the previous week. The muscle weakness improved incrementally after several months of treatment. No one was able to really explain why this happened but the suspicion is with early treatment decline, a phenomenon where severely B12 deficient patients get worse during treatment before better. Most I can recommend is make sure you're supporting the treatment process as well as possible with good diet, sleep, very mild exercise and supplementation where needed. I learned on this forum that my experience was not particularly exceptional and many do experience this early treatment decline although poorly informed doctors sometimes believe once you get a few B12 shots you'll be back to full health instantly. This is sadly misinformed and is only likely to happen with a mild and/or short-term deficiency.
Some doctors are familiar with B12 deficiency from Nitrous Oxide poisoning but this can be an acute phenomenon for which treatment is sometimes sought very quickly. With Nitrous Oxide identified as the culprit, injections are given immediately and its typical for patients who receive prompt treatment to have an almost complete recovery even when neurological symptoms were seen. The trouble happens when neurological symptoms are left untreated for weeks, months, years. The situation is then very different as a lot more damage is done to the body. Raising B12 levels is only the start of the healing journey in such cases.
all my pins and needles, burning, stinging and fatigue came back after surgery two months ago, prior to the surgery I was showing good improvement. When I reported it to the surgeon at my post op check up. And mentioned the nitrous oxide, She went “OH yes!”
I'd like to think that GPs in UK were more aware of the potential negative effects of nitrous oxide on B12 after recent news stories about young adults being badly affected even paralysed due to taking nitrous oxide as a drug.
I found some interesting articles when I searched online for "functional b12 deficiency nitrous oxide".
If I ever have to have surgery, I will be writing No Nitrous Oxide in big letters across whichever body part is being operated on or sending letter to hospital prior to operation.
sadly I thing the system is at breaking point and many are too tired to process the implications of what patients are telling them. They must get a lot of info from patients and sorting the wheat from the chaff requires an alert brain as well as experience. Hope you recover quickly.
thank you for taking the time to share this information. I will see about a further jab next week and see what happens - at least I now know what could happen. I have joined the PAS so I shall follow your advice - my GP is very good and I am very lucky - I saw her because my tongue kept swelling and I fell asleep at work a couple of times and six weeks later I am having B12 jabs. It’s all happened so fast which I understand is a blessing based on others experience. Thank you again.
I remember feeling so drained when I had my loading doses even though I felt awful having very low b12 to begin with.
You will need time to your self for your body to catch up and rest, it may take a while for you to feel better. People are different. For me it took a long time to figure out what my body was doing and I slept so much and I think that was my body catching up with the b12 replacement. Try keep your sleep routine the same if you can.
My sleep goes out the window when I'm due mine again but then I sleep right after I've had it.
Make sure you not allergic to the injections if your not it maybe your body healing. Hope you feel better soon xx
Thank you for sharing this. I will have to slow down then as I am usually in top gear most of the time and that’s where I have always been and where I like to be - but this PA has to be got under control so your advice is very useful. Thank you for taking the time to share this.
it could be one of the ingredients in the solution of B12.
I had a reaction to one particular brand of hydroxycobalamin. It had hydrochloric acid used as a ph balancing ingredient, my normal brand uses acetic acid.
that’s interesting and I will note that as something to consider as some jabs (other than B12 I am ok with and some I am not). I wonder if other jabs use these two balancing agents? Thank you for sharing your insight.
Please do not stop or postpone treatment. You must battle through with the correct set of loading doses. If you avoid the jabs you could create more long term health issues. The jabs are giving you short term pain that unfortunately you will have to endure to get better.
B12 is not like a pill or drug that makes you feel better. Its an essential nutrient that your body desperately needs and is working overtime to use up to fix you.
Recovery from many vitamin deficiencies causes a paradoxical effect. But you must not give up. Keep supplementing and enduring the symptoms. You will have to rest and recover
Thank you. I am beginning to realise that. I think the problem is it all happened so quickly with no supporting information and it was scary. Thank you for taking the time to share this
It is very scary to have a B12 Deficiency. You have all my sympathy, especially when Doctors know next to nothing about it really. So it's they who should insist that you follow through. And perhaps give you some medication to help you get through.
Testing times. But I do hope you'll carry on and push through with support around you. You can't have too much B12.
People who are B12 deficient may have too few red blood cells and/or unhealthy red blood cells.
When they get a B12 injection their body will go into a frenzy of red blood cell making. But red blood cells have numerous ingredients, not just B12. One of the ingredients for making red blood cells is potassium. So if the body makes a lot of RBCs then potassium can run low, and since potassium is extremely important to every cell in the human body, and is particularly important to the heart, a shortage can cause many unpleasant symptoms.
Once the body has caught up with making RBCs the need for more potassium than usual will disappear, until numbers reduce and you get another B12 injection.
You might find this article of interest. The comments are worth reading too :
One thing I have always wondered is what other ingredients are required to make RBCs that might cause unpleasant symptoms if their levels run low, but I've never been able to find an ingredient list.
Personally I don't need B12 injections - I don't have PA. I have a functional B12 deficiency, and can cope with it by keeping my serum B12 and Active B12 levels very high with oral supplements. One thing I did discover was that taking a small dose of potassium about 3 or 4 times a week helps to keep cramp away. It's been a bug bear of mine for decades.
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