Hi, I’m new here as i’m trying to research as much as I can about B12 deficiency and PA. I have a 14 year old daughter who has been complaining of feeling unwell for more than a year now. She was originally diagnosed with concussion syndrome but after weeks of crippling headaches and fatigue she never truly recovered. She is now at a stage where she is so unwell she describes the feeling as like she is dying, she has so many symptoms I thought she was just being anxious but I have been taking note of everything and trying not to worry her. She has had blood tests run by the GP and her vit d was deficient and so she started on vit d3 tablets but is feeling gradually worse as the days go by. Her B12 came back as “borderline” but I was told no action is required as it wasn’t enough to need treatment (171 ng/L). I’m now reading routine blood tests do not determine active and inactive B12 but do a full count of both so a reading is not a true picture of what is going on. Her symptoms are :-
extreme tiredness and no matter how much sleep she gets she’s tired
stomach pain / nausea / wind / diarrhoea
weakness in her legs and arms and even holding anything makes her arms burn
legs giving way and i’ve seen her jolt to upright herself when she feels her knees buckling
burning legs
dry cracked skin on hands
feeling faint all the time
headaches / vision disturbances
feeling like she has a weak bladder like she might wet herself so urinating more frequently
irritable
low in mood as feeling so unwell she’s lost interest in doing things she loves as she’s too tired to do them
I have an appt with her GP tomorrow to see her face to face but when I asked if her vit d deficiency (as it was only treatment he said she needed) would cause this he said i don’t know, we treat it and see what happens. If no improvement refer to paediatrics. As you can imagine as her mum i’m feeling desperate to get her help and looked into private blood tests for Total B12, Active B12, and methylmalonic acid but they are not for the under 16’s and I know waiting to see if the d3 helps and a referral will take time and she is on a downward spiral.
I’m looking for anyone with experience of a teen with symptoms and how you got them diagnosed and what blood tests you had done. I’ve booked a second opinion with a different GP but that’s not for another 3 weeks but I want to be armed with as much information as possible.
Thank you for your time if you are still reading and I hope I haven’t asked anything I shouldn’t. My mind is racing right now.
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Her diet isn’t great as she is a fussy eater, she loves fruit but not so good about eating veg. She doesn’t have fish as she always got stomach pain and threw up after eating fish when she was younger. I haven’t tried her on it since although she can eat and loves tuna, allergies to fish run in the family on her dads side.
I am looking to order B12 oral tablets from Amazon but I have no idea about dosages, the ones for her age are 2.5mcg. I am hoping the GP will offer further blood tests but i’m not hopeful as he’s not the most helpful and isn’t normally a GP i would see.
Does she eat meat at least three days a week (or every day if it's chicken breast).
Any tablets from Amazon should be OK. It's impossible to overdose on B12 and you can only absorb about 10 mcg at a time. It's probably a good idea to avoid methylcobalamin as some people have adverse effects from taking it.
The NHS also recommend that all women of childbearing potential should take 400 mcg of folic acid a day. I would suggest she starts early with supermarket folic acid tablets.
She used to eat meat / chicken at least 3 x per week but she has gone off so many things since feeling ill. She will still eat chicken happily it’s beef she’s struggling with.
I’ve just watched a video by Michael Greger MD and he recommends sublingual B12 as it is absorbed much faster when mixed with saliva?
No. The B12 molecule is too large to cross biological membranes unaided. Sublingual B12 works in most people because it is swallowed. It's exactly the same as oral B12.
If B12 could cross biological membranes without help then none of us would need injections. You could get more B12 into the body with sublingual lozenges or sprays than with injections.
If sublinguals allowed you to absorb 10 mcg from a 1000 mcg dose then a B12 suppository would allow you to absorb over 500 mcg (the amount absorbed depends on how long the drug is in contact with the membrane).
All the values reported are in picomoles/Litre. Multiply by 1.355 to convert to ng/L.
According to this article children's usual B12 levels are higher than adults.
If your 14 year old daughter's total B12 level is "borderline" according to adult levels, she is probably deficient.
It might be helpful to request an intrinsic factor antibody (IFAB) test. If this test is positive, it means your daughter very likely has PA and should start on B12 injections ASAP. Approximately 50% of people who definitely have PA return a negative IFAB test, so a negative result doesn't mean your daughter doesn't have PA.
PA is not the only cause of B12 deficiency there are many others.
The only reliable method for determining if a person is B12 deficient is to monitor the response of symptoms to a trial of B12 injections. B12 is harmless and cannot be overdosed.
Untreated B12 deficiency can result in permanent neurological damage, so if your daughter is deficient, it is important that she is treated ASAP. I think vitamin D responds very slowly to D3 supplements, so waiting for a response to D3 supplements might not be wise.
According to that article a teen between 15 1/2 - 19 should have a level of around 499 ng/L and my daughters is 171. I’m going to go to the appt armed with as much info as I can and hope that he might offer her a course of B12 and see what happens but i’m not hopeful as he’s not a GP to be challenged. If no luck then I will give her oral B12 and hope for the best but I don’t know dosages so it will be trial and error.
Oral B12 relieved my neurological symptoms very well for several years. I was taking 5000 mcg per day. Most studies of oral B12 for treatment of B12 deficiency use doses of 1000 mcg per day or higher.
Edit: My understanding from experience, from posts on this site, and from journal articles is that high dose oral B12 works for some but not all people. When it does work symptoms clear up slowly.
Oral B12 might increase B12 blood levels, then you will have more difficulty persuading your doc to give your daughter injections.
In my case oral B12 worked well for several years, then seemed to stop working; my symptoms slowly reappeared. I am now self injecting.
Ah, poor you and poor her I have twins who were B12/Vit D deficient whilst living abroad. Oral supplements worked for them. I have an older daughter who I was convinced was showing signs of B12 deficiency and she was diagnosed with hemiplegic migraine after first being erroneously diagnosed with ME by the GP. The Neurologist knew straight away what it was. I'd push for that referral to Paediatrics. Wish her well ❤️
Your GP must refer her. Meaning, I regard referral to a specialist as essential (not that he will just because you ask).
Please ask additionally for at least a thyroid test (you would want TSH and Free T4 and Free T3 - but just TSH is likely all that will be offered). Several symptoms could be caused by insufficient thyroid hormone.
I had a lot of those symptoms at around that age. It has taken me about 25 years to diagnose myself and get private treatment. I have never got any doctor to admit I was deficient despite paying for private tests and treatment.
I was repeatedly told ‘your test results are normal’ when they hovered just above the bottom of the range and I had many symptoms.
From my understanding MMA should be high if someone is B12 deficient without having PA so you could try asking for this to be tested. You can also pay for your own test but I think they are around £130.
Thank you everyone for your replies and help. I explained what I could about what I remembered about B12 and that the blood test that was done would not have tested her active and inactive B12 and if she has a high percentage of inactive B12 in her blood then as she was already borderline she could in fact be very deficient. He said he didn’t know anything about B12 and he had already decided to refer her to paediatrics as she has been unwell for over a year now. So it will be another 6-8 weeks if we are lucky for an appt for that.
I asked for further blood tests for the intrinsic factor antibodies and to test for active and inactive B12 and he said we will do that in 2-3 months but it’s something I should discuss with the hospital. I even mentioned about paying for it to be done and again was told that’s something you need to talk to the hospital about. So far all the private blood testing is for ages 16 + and she is only just coming up 15.
I’ve ordered the oral 50 mcg B12 and also 1,000 mcg B12 as it will do no harm to try. I just don’t want to affect any blood test readings which is why I was hoping he would have let me have those blood tests now.
I’m hoping once we get that referral we will see someone who will run more in depth blood tests for everything but I was told in the meantime if she gets worse to take her to A&E.
" if she has a high percentage of inactive B12 in her blood"
I have never, ever heard of this occurring apart from a very few cases where people have mutations in the TCN2 gene that codes for the transcobalamin protein. And that shows up in infancy because the effects ore quite drastic.
"I just don’t want to affect any blood test readings"
The only way taking oral B12 would affect blood test readings is by raising her levels of B12. Surely that is what you want to do. If taking oral B12 raises blood levels then that is the best news possible. It means she can keep her levels high without needing injections.
It’s what I had read and I was fighting her corner and trying to give reasons for more in depth blood tests. I’m very new to all this and finding my way so not a wealth of knowledge and experience and there is a lot of information as well as misinformation i’m sure. Its been frightening and still is when your child is so unwell and you have no definitive answers. I will start her on oral B12 as i’m not waiting any longer and of course if her symptoms improve as it raises her blood levels then I will be extremely relieved.
Hi @fbirder, I realise that in this case supplementation might work as it may be diet related but: Every trusted source I've read says not to supplement before being fully tested (and the haematology consultant I was referred to agreed that once I had supplemented, second line tests were no longer likely to be useful), so I don't really understand why you say this fbirder ? Aren't symptoms more important than blood levels? Not trying to be cheeky, I just want to know why you seem to disagree with what I've come to consider as the consensus among B12 knowledgeable sources!
There are three possible situations - a dietary B12 deficiency, a B12 absorption problem, or no B12 problem at all.
If you test now and serum B12 is still 171 ng/L; 'Active' B12 is 50 ng/L and MMA is 180 nmol/L then you have two borderline tests and one that suggests no deficiency.
What do you do?
Option 1. You can give injections for life. You wait to see if there is a significant reduction in symptoms. If the symptoms are reduced then you conclude - there was a deficiency. But you don't know the cause, dietary or absorption problem. So you need to give injections for life, or stop them until the B12 blood levels drop back to their low-normal and symptoms return, switch to oral B12 and see what happens.
Option 2. You trial oral B12 for three months, then you check Serum B12, 'Active' B12 and MMA. If all three are normal (high normal for B12) then you know there is no absorption problem and wait to see if oral B12 relieves symptoms.
Note that Option 1 and Option 2 do not rely on having already tested. If you just use the borderline result of 171 ng/L you would still follow one of those paths. 'Active' B12 and MMA tell you virtually nothing.
Coeliac is another test have thought about as on reading her bloods report it states she has selective IgA deficiency, her level is 0.06 g/L when it should be between 0.80-2.80 g/L
You’ve already been given some great advice and guidance, but I just wanted to say that I have PA, I suspect my dad has it, and one of my daughters was diagnosed with it last year. She is 22 now, and even though we knew there can be a genetic component, it still hit me like a ton of bricks! If your daughter does have a B12 deficiency, this group here and the PAS are an amazing asset you’ll have to make sure she gets taken care of. You’ll get all the support and guidance that you need, from people who can relate. It’s amazing that you’re standing up for her, trying to get to the bottom of what’s bothering her. I’m sure she thinks you’re amazing! There are a lot of moms that write off their kids complaints, thinking their kids are just weak, and it’s not right. I hope you get the answers you need to get her feeling better.
It sound as if you will have a struggle getting help from your GP. In my opinion it might be best going down the oral B12 route. They are cheap and very easy to buy. If they don't work then you can pursue a medical diagnosis. Oral B12 works for me and many others on this forum. Oral B12 supplements can only be absorbed passively and only about 1% of the B12 supplement will make it into the blood. The process is basically osmosis. So you need to take lots. The body can only efficiently absorb a small amount of B12 within a given period of time. In order to help B12 absorption it is recommended that you divide the dose over the course of the day. So I buy 5000mcg liquid drops and dilute them with water and drink it regularly throughout the day.
I started this protocol over 3 months ago and since doing this my recovery has been remarkable. I could get injections but I won't bother. I'm a big coward and I feel the oral B12 gives me much more control over my situation. For example if I exercise a lot I find I have to take extra B12.
Best of luck with your daughter. You seem well read and very determined. Your daughter is lucky to have you as a mum.
Thank you for this, I like the idea of liquid drops so you can spread the dose out throughout the day. I’m hoping she will improve with B12 as her symptoms are a mystery to the GP and it’s hard watching her go through this.
"Oral B12 supplements can only be absorbed passively"
No. In 99% of people B12 can only be absorbed via the Intrinsic Factor mediated route. In people with PA they can't make IF, so they cannot absorb oral B12 - at all. That is why they need injections.
How long before someone would show improvement when taking oral B12 if they don’t have PA or is it one of those things that affects everyone differently? If no improvement then the only way to know if it’s PA without testing is injecting?
After a month I would expect to see some improvement - if the problem was a B12 deficiency. If blood levels rise significantly on oral supplements (up to twice the bottom of the normal range) then I would look for other causes.
I showed massive improvement within 3 days. My neurologist said this was quite normal. If you don't see any improvement within a week the oral B12 isn't working and your daughter will have to have injections. But the initial dosage of oral B12 must be very high. At least 10,000mcg to allow enough B12 to enter the bloodstream by osmosis. Just like loading injections. You cannot overdose on B12.
Above summary indicates that patients who are symptomatic for B12 deficiency should be treated even if serum B12 level is within range, to prevent neurological damage.
The actual quote is
" In the presence of discordance between the test result and strong clinical features of deficiency, treatment should not be delayed to prevent neurological impairment"
Low dose cyanocobalamin tablets are sometimes used to treat dietary deficiency in UK.
My understanding is that severe B12 deficiency with neuro symptoms should be treated with B12 injections in UK whatever the cause. I'm not medically trained.
I've written some very detailed replies with more B12 info eg more B12 articles, more B12 books and websites in threads below which might be of interest.
Yes I am in the UK, the GP we saw didn’t know anything about B12 but at least he admitted to it and referred her. I said to him she has so many symptoms all over the body that I know it’s a mystery but all of her symptoms come under B12 deficiency so it just seems likely as she is borderline and slightly under the lowest level they test for.
There may be separate local guidelines for children and adults.
Doctors may say they have to stick to the guidelines...
I suggest asking which guidelines they are referring to and asking politely in writing for a copy of them or submitting a FOI (Freedom of Information request) asking for a copy.
In UK, GPs and other doctors are allowed to prescribe off-license if they feel it is in patient's best interests. See article below.
NICE has changed its guidance on ferritin ranges so your GP may be interested. It might take a long time for any change in NICE guidance to filter down to local reference ranges.
Above link says "In all people, a serum ferritin level of less than 30 micrograms/L confirms the diagnosis of iron deficiency."
I do not know if the above statement applies to children.
ug is the same as mcg (microgram)
Folate borderline, ferritin borderline (maybe even below range) and symptomatic and borderline for B12 deficiency...
Are they going to test for Coeliac?
There are two usual first line tests for coeliac
tTG IgA and Total IgA
You mentioned she had IgA deficiency so my understanding is that she would need different tests. See link to coeliac guidelines in other reply.
It's also my understanding that people who need testing for coeliac are usually asked to eat plenty of gluten in the weeks before blood is taken. I think this is to ensure that a coeliac patient will have plenty of antibodies to gluten in their blood.
If Coeliac disease is a possibility, I suggest talking to Coeliac UK.
If PA is a possibility, I suggest joining and talking to PAS (Pernicious Anaemia Society).
More about causes of B12 deficiency
Diet
Might be worth writing out a typical weekly diet, food and drink as GP/paediatrician may want to know and noting any recent changes to diet.
Foods that are rich in B12 include fish, shellfish, meat, eggs, dairy and foods fortified with B12.
Other possible causes of B12 deficiency include PA, Coeliac, Crohn's disease, damage to terminal ileum (part of gut where B12 is absorbed), H Pylori infection, some medicines and drugs, exposure to nitrous oxide (also known as laughing gas) and internal parasites eg fish tapeworm plus others.
Has your daughter eaten raw fish/uncooked fish in past or lived or stayed in an area where internal parasites are common?
Fish tapeworm infection can lead to severe B12 deficiency. One potential sign of fish tapeworm infection is an increase in eosinophils, a type of white blood cell. Eosinophil result can be found on Full Blood Count results.
Another internal parasites that can lead to B12 deficiency is Giardia Lamblia and some other types of internal worms.
Has she ever been exposed to nitrous oxide?
This is sometimes used as part of anaesthesia/pain relief during operations.
I would add that I think I have an absorption problem. I am in the process of excluding gluten. I have been reluctant to entertain this previously and have tested negative for coeliac.
I started taking b12 supplements before my initial private tests showed a result of 227 which is too high to be considered deficient. Previous tests show a steady dropping from 400 to around 300 to mid 200s. I believe I had symptoms even at these 'high levels' as I was frequently tired progressing to numbness and nerve pain.
I don't know what to suggest. You can pay privately for b12 injections in some clinics. The chain I used was called REVIV. The benefit of this is that they will treat you quite happily and the one I went to was staffed by ex NHS nurses. I'm not sure if they have any age restrictions. It is quite expensive at around £27.
Eye pain is exactly what my daughter has been describing, she always said she had a sudden headache but when she described it it was more eye pain and last night she suddenly tells me she’s had this really annoying ringing in her ears for weeks!
Is there any possibility she has had covid? There are a lot of weird and wonderful covid symptoms many of which could be linked to nerves. I was sick around the same time I got vaccinated and I do wonder if I could have had covid. I haven't had any issues with eye prior to that.
The oral B12 50 mcg I ordered is arriving today, I’m reading that the body only absorbs about 10 mcg of that so I’m thinking it’s ok to give more than one a day to bring her levels up so maybe one a.m. and one p.m.
I hastily ordered a 1,000 mcg dissolve under the tongue B12 but i don’t think that will have any better benefit than taking the 50 mcg?
Interestingly I just found out that my niece is B12 deficient and has been told she needs injections for life although they never tested if she had PA or an underlying condition to prevent absorption.
Let us know whether she sees any improvement. I think there is a lot of disbelief in doctors that a 'vitamin deficiency' could cause such bad symptoms.
She was off school Friday as felt so bad and legs keep feeling like they aren’t working properly. We have a meeting Monday to discuss shorter days to help her until we have some answers.
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I have twins who were B12/Vit D deficient whilst living abroad. Oral supplements worked for them. I have an older daughter who I was convinced was showing signs of B12 deficiency and she was diagnosed with hemiplegic migraine after first being erroneously diagnosed with ME by the GP. The Neurologist knew straight away what it was. I'd push for that referral to Paediatrics. Wish her well ❤️
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