After having my loading injections stopped by the GP because the nurse decided to take my bloods straight after my first injection which resulted in a result of >2000 I had to wait 4 weeks to be tested again.
So had bloods taken yesterday, GP called yesterday about 5pm to say the consultant she spoke to says there is no way that the first injection affected my blood results, so my level must of been over 2000 before my injection. I asked how that is possible if my level was 224 in October, her words were I don’t know!
So now my level is 800 and she says that’s a normal result. She has no interest in the fact it could be b12. Has referred me for a brain mri as her biggest worry is that there’s something wrong in the brain. Although she doesn’t know how long it will take to get an mri.
can anyone tell me how long I need to wait to get tested again after the 2 injections 4 weeks ago for me to get a true reading? Thanks
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I don't know what consultant your GP talked to but they really didn't know about B12 if they said that the first injection wouldn't have affected your serum B12 level. The whole point of using injections is that it puts huge amounts of B12 into your blood, and though on average this lasts for 2 months with hydroxocobolamin and 1 month with cyanocobalamin it can linger for years in the blood. The previous NICE guidelines do not recommend retesting once treatment has been started unless there is a suspicion that the patient isn't complying with treatment - not something that will happen if the treatment is injections.
The test is measuring all of the B12 in your blood, not just the B12 bound to the protein that allows it to pass into your cells..
I'm not as familiar with the new NICE guidelines but it sounds to me as if your treatment isn't complying with them.
I hope that Sleepybunny can respond with references that you could use to explain to your GP that what they are doing is wrong. Writing to your GP with a copy to the practice administrator asking that you be treated in accordance with current NICE guidelines which I am sure will include that treatment shouldn't be based on repeating serum B12 after injections have been started as it is a difficult test to interpret before treatment and impossible to interpret in terms of how well your cells are doing with B12 after treatment starts.
I'm surprised that the result was over-range at the time of the first injection, but it shows how pointless it is measuring B12 once therapy has commenced. It wastes your time, the nurse's time, the lab's time and adds no value whatsoever.
You'd been put on loading doses, so that ought to have happened regardless.
At least the GP admitted she didn't know!
If you've been found to need B12 injections, then there's no point or value in performing more B12 tests once treatment has started. Once more, and I repeat
'Treat the patient, not the numbers!'
Performing tests that you don't agree to is not only a waste of everyone's time and NHS money [as in OUR MONEY], it's assault.
I think my problem is the GP has never actually been convinced my b12 is the issue. I was the one who asked for the loading doses due to my level being low but not outside the normal range, she wasn’t convinced that my level would be causing my symptoms.
My argument was why can’t we trial them, as it could be that rather than MS which is what she is convinced is the issue . My intrinsic was negative jan 24 and she said the lab won’t do MMA testing.
Obviously NICE guidelines are that she should be treating if levels are 200-350 but she is adamant my level was over 2000 prior to injection, so I have no way of fighting her on that.
She doesn’t know, I was referred to neurology in September but was told it could be over a year before I am seen. She has now been able to refer me for a brain mri before the neurology appointment. She just keeps saying that she thinks there’s something wrong with the brain.
She’s obviously not that concerned, my referral to neurology apparently was only a routine referral. But she’s now sent an urgent but said it might be rejected. I had a CT scan in December in A&E as they thought I was having a stroke. But it was clear. They just keep giving me nerve tablets, which did nothing.
Yes it was very scary. The CT scan did reassure me there wasn’t anything obvious. I think I’m going to have to self treat as she’s not even interested in testing my levels in a few months. That’s not the route she is following unfortunately.
The MMA IS THE BETTER TEST . Also a homocysteine test is valuable . ( it is not only applicable to B12 deficiency I know , but a useful test nonetheless) It is acknowledged in the latest NICE guidelines ( March 2024 ) that a negative intrinsic Factor test result does not have to mean that you don’t have P.A. SYMPTOMS ARE THE MOST IMPORTANT CRITERIA . Has your GP read the latest guidelines ?
According to her the lab wouldn’t do the test. Said they won’t do it on the nhs, she doesn’t think my symptoms are b12 related. Regarding NICE guidelines, I quoted a lot from them but to be honest I don’t think she really knew anything regarding b12. They just all seem to be concerned if your level is outside their range. On my blood results it also stated normal, no comments regarding deficiency.
100% spot on and clinical research - peer reviewed and medically accepted research - supports checking MMA, and also, homocysteine, to use as a way of determining whether macrocytic anemia is being caused by B12 or folate regardless of serum levels. Also get a full iron panel to include iron saturation and TIBC since iron anemia is microcytic anemia, and you can have both micro and macrocytic anemia, which will render your blood labs appearing normal since MCV etc. will fall dead center in this anemia tug of war. Ferritin can be high if you have inflammation anywhere which means UTI, gut infection, tooth infection, allergies, etc.
Last full bloods I had done were October 24. I think my ferritin is low but GP disagreed. Was given folic acid for my low folate. A months worth, but was given more at my appointment in January.
You have every lab value indicative of macrocytic anemia. The question to answer is "why"? Is macrocytic anemia due to malabsorption, vegetarian diet, alcoholism, gut infection, not enough leafy greens? Look over your medical history - your labs - to see if you've had the same results over time or are these results new to your current labs. Following are indicators of macrocytic anemia: Low hemoglobin. High end of normal MCH. MCHC is high. All are indicative of macrocytic anemia or B12 and folate anemia. Your iron is on the low end which is likely due to low folate as iron requires folate. As for 2K+ result? The liver stores B12. Your liver (hepatic) labs are awesome! Therefore injection into liver - raised to 2K - and released into system to be used expeditiously and once again B12 low. Better yet your liver can handle more B12 injections (to remove concern from your practitioner point this out). You also need to adhere to daily folate as prescribed since it was very low. B12 needs folate as a transport. Your nurse, your doctor, they work FOR you. You PAY them via taxes. Use this to give you confidence when standing in front of them sharing your clinical data and demand at least 6 months of weekly B12 injections and continued folate. Optimal labs are in the middle. Not high or low end of normal. Not high. Not low. Smack dab in the middle is normal and healthy.
Thank you. It’s a lot to get my head around. I just don’t understand how you have pointed out all those indicators in my results. Yet my GP is ignorant to it all. This is the third GP in my practice I have been to, and finally thought I was getting somewhere when she agreed to the loading injections. Surely it’s a quicker easier solution than referral to a neurologist and cost of MRI, tests etc.
It’s actually scary how many people are being misdiagnosed. My GP makes me doubt myself even though I have done the research. So walk out of the appointment thinking I must be wrong.
Never doubt yourself. It's been a long journey for all of us here to understand why we feel less than optimal and thus we have all become students, obsessive researchers, of anemia to include objective (eg lab work) and subjective (eg tinnitus, balance problems) related symptoms. Always keep in mind your doctors/nurses report to a business office and get in trouble if they treat outside of guidelines to include lab values still within "normal" range. They aren't lazy per se they just want to keep their jobs, have great performace ratings to get pay raises, and this is done via keeping costs low by minimizing labs/diagnostics/medicines. Therefore you need to provide them clinical evidence of the need to treat you adequately. You need to educate them to remove any concern to properly treat you and not get in trouble with their business office. A general practitioner and a nurse are not specialists. They are generalists. This is why they don't know what they are looking at - or the risk of inaction - unless a lab is outside of range. My advice? Get a referral to a hemotologist (blood specialist). They should know right away how to treat you. If you cannot do this then to your nurse or GP, 1. point out your lab values that clearly indicate anemia of the macrocytic kind (B12 that dropped back to 200 after 2000 = your body is depleted and low folate, and also, labs referenced in last response), and, 2. that your macrocytic anemia is now impacting iron which is why your platelets are on the lower end and MCV is also not higher (macro vs. micro keeping it in mid-range). Once you address B12 and folate your iron should come back up. Lastly, is there anything you have experienced and/or are doing that might result in B12 and folate anemia - no need to respond - just be self aware these are culprits: 1. family history of B12 anemia (mom or grandmother with dementia, frequent falls/balance issues?), 2. are you a vegetarian, 3. do you have stomach issues (burping/diarrhea/gas), 4. do you drink a lot of alcohol.
Thank you for such a detailed reply. I have typed up a letter which I will send today, the gp did say they had spoke to a consultant but not sure if that was a hemotologist or not. But I have requested to be referred if she can’t explain my levels.
I do have family history of PA, but the GP is aware of this, and i also have ongoing stomach issues, ibs, and for the past 6 months extreme burping, I am already on lanzoprazole which I have been for years, I did mention this as well to her but that was brushed aside, she is just fixated on my level not being outside the range. Hopefully my letter might help, I am going to print off some sections of the NICE guidelines to send with the letter, so fingers crossed.
Lanzoprazole, all PPI's, are known to trigger B12 anemia (reduced absorption of B12). Metformin as well as an FYI. This is well-documented and known. Your stomach issue might actually be autoimmune gastritis which is the precursor to full-blown PA and not high stomach acid. If high stomach acid 2 weeks max of lanzo would have sufficed. So, to get to the root cause of all of this, have your serum gastrin level checked (fasting lab): 1. If low, that is normal and not PA just B12 anemia caused by taking PPI for too long, or, 2. If serum gastrin high this is yet another indicator to suspect PA. The other labs you should check are homocysteine and MMA (methylomanic acid). These are not frivolous labs, they are the only ones to provide solid evidence-based medicine that point to B12 anemia. I burped all the time, digestive mess, other symptoms, and was told it was menopause related aka "go away it's just menopause" aaarrrghhhh! ;). I have B12 anemia and digestive issues were gastritis. Also have a family history of PA. Other symptoms include tinnitus/hearing loss, balance issues, vision issues (severe floaters/flashes), cervical spondy, and fatigue. All gone with B12 injections except mild hearing loss remains. I live in the USA where PA is rare, and had to learn about it on my own which led me to this site. Demanded B12 vials and syringes to self inject which doctor agreed to. Finding I need an injection every 2 weeks and have done this for 1 year so far. Now trying to space out to every 3 weeks. Trial and error. Keep us posted ok? It is truly a pain you have to do all the work but 100% worth it to get better.
The lab rejected the MMA test that the doctor tried to get. The nurse who actually took my blood said it was a new test to her, she hadn’t heard of it before. I was actually the one who asked the doctor to test it.
How can I get the doctor to test serum gastrin level?
So did you get diagnosed with PA? I have everything to self treat, but I really want to know exactly what’s wrong with me.
I have drafted a letter which someone had suggested, so will wait to see what the response is to that and then decide I think.
Thank you so much for all your knowledge and help.
A lab is able to deny the request of a doctor? In this case, a guess on my part, it would appear the lab will only approve this more specialized lab by a specialist or hematologist. Is that correct? I've never run into a lab denying a physician request (reside in the USA). I personally check MMA to know if I am on track with B12 dosing and frequency. High MMA = elevated homocysteine = increased cardiovascular-related health risks so I check this once per year.
That said, and this will remain your frustration as it is perhaps for all here, there truly isn't a conclusive PA or B12 anemia diagnostic. There are, as pointed out, several labs that when pieced together enable a likely conclusion. In your case it appears the cause is either the PPI or genetic. I do not have a conclusive PA diagnosis, only a strong indication this is the case after labs and symptom resolution with treatment.
For example, my most severe symptom after a long time of being undiagnosed because I wasn't ever tested for B12, was cervical spondy. I could barely hold my head up and had severe neck pain with no obvious cause. It was this symptom that pointed me towards learning of B12 anemia as a potential cause, and then recollecting my maternal grandmother had regular B12 injections. Long story short when I finally started B12 injections cervical spondy resolved and has not returned.
Something to consider if you have not already done so is to stop taking the PPI (lanzoprezole correct?), wait a few weeks, and get another B12 lab. Rule out the PPI as a cause of your B12 anemia.
You could go it alone and SI. If your symptoms start to improve, remembering that they could get worse for while, then you have the evidence. It was how I convinced my NEW GP practice to join in my treatment.
If there is no change, let the GP do the tests. Or let them do the tests anyway while you experiment. I remember how hard it is to take control when you're in the thick of it all.
It'll cost a couple of pounds a day, won't do any harm, and should give you the answer one way or another.
I’m seriously considering self injecting. I have everything sitting ready to go. I just have this part of me that wants to wait it out and prove them wrong. I just don’t know if I can last another 3 months.
So did you tell your doctor you were SI? I’m not sure mine would understand as they were so against my level being over 2000.
This is the 3rd GP I have tried at my practice, who I thought was good when she agreed to the loading doses, but that obviously changed.
I changed GP practice about the same time I started to SI. I didn't tell them until I had a list of fixed and outstanding symptoms to hand over.Then I went in and gave them a choice of joining in or me just going it alone because I wasn't going to stop. I pointed out that I should have been treated by the NHS from day 1, and indeed should have still been on eod loading based on their own guidelines.
They agreed to 3 monthly injections. I still SI as symptoms dictate. At least it's on my records, in case they ever work out that a few jabs are cheaper and more effective than expensive test, scans and anti depressants.
I could change surgery, but I really didn’t want to. I might look into it though. Amazing that you managed to get them on board.
Well today I woke up and thought what’s the point, I could be fighting this for months and still not get any further forward. So I done my first injection! I’m still going to send my letter to them regarding them explaining my high level not being caused by my first injection. And if they ask I might tell them I am paying for private injections.
Good for you, I hope that you start to feel better soon. I think that you’re right to keep fighting though. You shouldn't have to jump through their hoops to get what you need.You’re not doing anything illegal, why not be honest? If you want to inject yourself that's up to you, and you did try and get them to do it.
Definitely if your symptoms start to clear up, make sure they know.
Good luck! I'd like to know how you get on, if you're happy to let me know.
Don't forget you can legitimately refuse all B12 testing now that you're injecting, citing the NHS own guidlines. Most of us here have been pushed for retesting at some point. Despite refusing, I had to physically cross it out on my last blood test sheet!
To my knowledge you should have received 6 loading doses and I was told my levels couldn't be checked for 90 days and there was no point in testing after injections as this will always be high, but monitoring is used to see how much it has dropped in a set time, along with trying to find out why its happened with intrinsic factor testing.The thing this forum has taught me if that professionals aren't knowledgeable around b12 and don't seem to care to want to be.
Quote the nice guidelines around treatment for b12 and point out to them what should be happening.
I had 6 loading doses, within 4 days my symptoms had returned and my neuro symtoms still remained. I sent a message into my gp quoting the guidelines and they gave me 1 more week of loading doses without a dr reviewing me. It has been harder since then as they have stopped treating me, although neuro symptoms remain, which again is not working to the guideline.
I can’t quote the guidelines because she thinks my level was over 2000 before my injections started, and the consultant has backed her up with that. How my level has went from 224 to over 2000 between October- January she doesn’t know! Yet 4 weeks after the injections it’s down to 800.
Oh sorry I've got confused myself. That is so strange, it doesn't seem right 😣🥴. It seems to have dropped rapidly though if it was 2000 to 800 in 4 weeks
It doesn’t seem right does it, when asked how my level could go from 224 to over 2000 in the space of 3 months she replied maybe you were eating a b12 rich diet!! As I have had no supplements.
To then get 2 injections and 4 weeks later it’s down to 800.
I actually think she doesn’t know much about it all so she’s pushing the MS.
Its almost like shes read the results wrong initially. Especially if you weren't taking any supplements, seems like a big jump even if you were on a b12 rich diet. I understand how you feel its deflating enough when you aren't feeling great to have to be fighting against them.
For over a year now Iv had numbness on right had side of my body and face. pins and needles in hands especially at night, wakes me up as if i have been lying on them. Random sharp pains in my legs. Insomnia, internal vibrations, headaches. It was all put down to migraines. I was feeling worse in January so she had wanted my levels done again before starting the loading doses but as I said the nurse took the bloods after the injection. So I don’t know if my level had dropped more or not.
Although from what I've read B12 deficiency effects are usually symmetrical, some forum members report symptoms that affect only one side or symptoms that are worse on one side.
I think many GPs find it easier to look for anything else other than agree that you are B12 deficient and need regular injections. It's their attitude about needing B12 that annoys me, won't listen to our sensible arguments. They don't know much about this deficiency, but they should x
Yes exactly if I can go online and research surely they can. She knows I have researched it, I went into my appointment with print outs, apologised to her that I didn’t want to contradict her but she was wrong. I cried during my appointment as well. She was very sympathetic but just kept saying I need an mri and a lumbar puncture. I’m happy to have the mri, but whilst waiting on that I’m struggling so much.
I don’t understand why they are so hesitant to accept it could be a vitamin deficiency.
No I don't understand either. It's like stubbornness, that they don't want to admit it. As you say, we've had to research it to help ourselves and they should too. I'm sure they've been told to play it down , worried about treating everyone who needs injections, which is really wrong.
The 2000 confuses me. What is the doctor’s proof, is it from a blood test and were you on oral B12 supplements before the test? If it was from a test, have seen all the results that came back and if not you’re legally entitled to a copy of them so ask for a copy. Whenever a blood test is taken every one should ask for a copy, ask also for a copy of your medical notes (you’ll likely need to fill in a short form for the medical notes).
I wasn’t on any supplements before the blood test, the nurse decided to take my bloods after she had given me my first loading dose injection. So within a few mins she took bloods from the same arm she had injected me. But GP is adamant that the injection wouldn’t have affected the blood test, and has spoken to a consultant who has said the same. So she won’t budge on her stance on it.
Even though she can’t tell me why my level could be that high.
I have a copy of the results yes, and it does say >2000
Here’s a polite but firm letter you can send to your GP practice manager regarding the issue. You can adjust it as needed to suit your style.
[Your Name]
[Your Address]
[Your Postcode]
[Your Email] (if applicable)
[Your Phone Number]
[Date]
[Practice managers name]
[GP Practice Name]
[Practice Address]
[Postcode]
Subject: Concern Regarding B12 Blood Test Results
Dear [Practice Managers Name],
I am writing to request further clarification regarding my recent blood test results for vitamin B12. On [Date of appointment ], my blood was taken just minutes after receiving my first loading dose injection, from the same arm. The result showed a B12 level of >2000, and I understand that [GP’s Name] believes the injection would not have affected this reading. However, I am struggling to understand how this conclusion was reached.
Could you kindly provide clinical guidance or evidence supporting the view that a recent B12 injection does not influence immediate test results? It is my understanding that such a test so soon after an injection could be misleading, as the injected B12 may not yet have been fully distributed in my system. Given that no alternative explanation has been provided for my high result, I would appreciate clarification on how this conclusion was made.
To ensure I receive accurate and meaningful results, I would like to request a repeat blood test at an appropriate interval, ideally from the opposite arm and after a suitable period post-injection. If you remain unable to offer an explanation for the unexpectedly high reading, I would also be grateful for a referral to a specialist for further assessment.
I appreciate your time and look forward to your response. Please let me know how best to proceed.
My serum B12 was 6000 and I feel pretty fine so I'm in no hurry to stop self-injecting once a week with 1mg. That said my 'active' B12 was middle of 'normal'.
GP's are often very poor scientists and dont propperly read guidance. The NICE guidance essentially says stop testing B12 once you start injecting and manage the condition based on response of symptoms. Saying that injecting B12 wont change serum B12 seems bone headed stupidity.
Search for "Wolffenbuttel B12 deficiency" to find other articles he's written, including one for Mayo Clinic in US and one for BMJ (British Medical Journal).
His most recent article (2024) was a review of best practice for diagnosis/treatment of B12 deficiency. Might be a good one to pass to GP.
Search for "Wolffenbuttel 2024 B12 deficiency" to find it.
In my personal opinion he's one of the few doctors who understands B12 deficiency.
4) B12d.org have interesting online talks about B12 deficiency.
I think these are aimed at both health professionals and patients.
I left very detailed replies in the threads below eg links to help those struggling to get adequate treatment for B12 deficiency in UK, suggestions of UK health documents to read, other B12 websites etc
No one on this thread has suggested that maybe the lab has made a (recording?) mistake. Could this be possible? Or a recording mistake further along the line.
Not quite the same thing, but a nurse was doing my annual check and must have got the figures mixed up. What went into my notes would have killed me if true? Nobody noticed 😱🤣🤣🤔
Oh something I hadn’t thought of to be honest, I would imagine now that I have had 2 injections I will never know for sure, as my level is now 800. So frustrating as I have been so careful to not have any foods etc with added b12 so that it didn’t affect my results. Now im back to square one unfortunately.
It is against guidelines to test levels after a B12 injection. Your high result is super normal for that. It is nothing to worry about because you had 224 before the injections. High B12 can indicate some very serious health issues. High B12 after injections indicates your doctor is an idiot who does not know what they are doing because it makes no sense to test once you start injections. Do not let them test again. Go back to your loading doses. You might have to self-inject if your doctor is not cooperative.
unfortunately I can’t go back to my loading doses, due to the doctor saying my level must of been over 2000 before I received my first injection.
Although as you say high levels can indicate serious health concerns, if my doctor doesn’t think the level was because of the first injection then surely she should of been trying to find out why it was so high.
I think she is trying to cover for the nurse who took my bloods straight after the injection, as she did contradict herself by saying she really wanted the bloods done before the injection.
I'm sorry you're going through this. I had one GP take me off injections entirely despite me having been properly diagnosed with PA because my blood levels were "too high". I finally got another doctor to reinstate them after a few months but I was a mess again by the time they did. I have coeliac disease as well and B12 is part of the panel. They tested it at my MOT last year and I had an argument with the nurse when she said I was wasting the B12 and NHS money because my levels were so high I clearly didn't need it every 8 weeks! I printed off the information sheet about the pointlessness of testing from the Pernicious Anaemia Society's website and dropped it in for her to read. Next time I saw her she was excited to tell me she'd found it so interesting she did some research on it and did a presentation to the surgery staff and clinicians about not testing B12 in patients on injections! I was gobsmacked. But really pleased. I've just had my bloods done for my coeliac panel this year and refused them permission (politely) to test for B12. The phlebotomist was a bit taken aback and had to go ask someone about it but came back and said that was fine, no problem, it won't be tested. I don't know if this helps, but you're not alone. Good luck with everything, hope you get some answers and some help.
Thanks you for that, I have printed off a few of the fact sheets and will include them with my letter, I’m not sure how much it will help me but it’s worth a try.
At least now you know they won’t try and stop your injections again. You would think we were asking for some really expensive drug the way they react!
I’m struggling to understand why doctors don’t know all this information, a quick google and it is there in black and white.
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Gp review after b12 stopped 
B12 injections stopped
