As most people here know, throughout the COVID lockdown I wasn't able to get my B12 jabs. I was told by my doctor to use oral tablets as a replacement until could get booked back in. I did so, but found symptoms of tiredness/light headedness/weakness start to creep back in.
I finally managed to get my much needed jab in late June, and started to feel better pretty quickly. Then, after about 4 - 6 weeks, I started to feel really, really tired/dizzy again. This was actually worse than I've experienced before.
The symptoms seemed so similar to what I'd had in the past before having my B12 jabs, I was convinced it was something to do with my B12 levels, and the 6 month gap I had due to COVID. I decided to go back to the doctors, and had a full suite of blood tests done.
After my blood test, I decided to get some B12 oral spray which I had recommended by a friend - it arrived and I started taking it immediatley. WIthin about 4 - 5 days I felt almost completely back to normal.
I then received my blood test results back from the Doctors (they retested my B12) - and it came back saying my Serum B12 level was >2000 at the time of taking (normal is 200-900). The results mentioned a high level can be the result of B12 injections.
So, I stopped taking my oral spray immediately for worry of 'overdosing' (though I'm not sure if that's even possible?).
2 - 3 days after stopping, the symptoms of light headedness and fatigue have returned.
I'm really not sure what to do - my Doctor advised not to take the oral spray. Yet, reading online there are a lot of articles talking about Doctors really not understanding B12 deficiency at all.
What's more, I read this article: stichtingb12tekort.nl/weten... - which states that B12 serum value does not reflect people's symptoms - and that different people need different amounts of B12 to feel normal
Curious to know if anyone's in the same position and has any advice? Should I continue taking the oral spray contrary to my Doctor's advice? Or should I wait until my next jab?
Thanks!!
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Probein
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Injections every 3 months - i've found I normally start to notice symptoms after about 8 weeks. This time the symptoms came on quicker, but wondered if that could be linked to the big gap I had between jabs due to covid (6 months).
Probably. That's why such a shame as only 3 monthly you didnt get it I'd push for 2 monthly. Bnf guideline which doctors have say 2-3 monthly. My daughter struggles at 9 weeks so has asked for 2monthly now.
Hi Probein personally I have been using an oral spray every day for about three years and have had no adverse side effects and I have my B12 injections every three weeks having had P.A, for over 48 years.
You don't say what the cause of your B12 deficiency is but if the spray is effective than that is all to the good as you cannot "overdose" on the vitamin as any excess is excreted via your urine.
Thanks Clive, that's good to know. My doctor hasn't ever diagnosed what causes my deficiency, despite me requesting to find out - I was just given a 'it just happens to some people' explanation.
It could be entirely placebo, but like I said I felt pretty much totally back to normal after a week of the spray...
You spray directly into your cheek, and my understanding is it absorbs into your blood stream from there, so for people who can't absorb B12 from food due to things like PA it allows them to get the B12 into their system. That's as far as I'm aware, but of course I might be wrong.
To be honest the differences between oral swallowed as tablet and oral that is dissolved in the mouth prior to swallowing are very minimal - fractions of a % in favour of dissolving prior to swallowing. If you are talking about very very high doses 20000mcg+ it might have an impact.
More significant than the difference between sublingual and swallowed is the variation between individuals in how much is absorbed. Average is 1% but for some its more and for some it is much less.
Why do the oral sprays work better than tablets etc?
They don't. They work exactly the same as the tablets. Because the B12 molecule is too large to cross a biological membrane.
Tests on, so-called, sublingual B12 show the same amount is absorbed as from an oral tablet - about 10 mcg from a 1000 mcg dose. But if some was absorbed from the lining of the mouth then you would expect more to be absorbed.
Let's imagine that B12 could pass across the membrane of the mouth. If 1% of the spray was absorbed then 99% of it is swallowed. But 1% of that 99% should be absorbed from the gut by passive diffusion. Leaving 98% of the original dose, 1% of which would be absorbed by the normal IF route.
So you would expect to see 30 mcg absorbed.
You don't. You see about 10 mcg absorbed via the Intrinsic Factor route. Meaning 0% absorbed by passive diffusion in the mouth and 0% absorbed by passive diffusion in the gut.
Thanks Fbirder - I've read some stuff that conflicts with this though, eg:
To address B12 deficiency, doctors often prescribe supplements to be taken by varying routes, including oral sprays. The use of oral sprays allows for B12 to be delivered directly into the mouth, to permeate the highly vascular tissue of the mucous membrane lining. As a result of this, the vitamin can directly enter the bloodstream. This route of administration is particularly useful in patients who find it difficult to take B12 in liquid and tablet forms.
Yes, and their sources are the same, poor quality, trials that most people call 'stupid'.
They actually state the reason why you cannot absorb B12 passively - "B12 is quite a large molecule, and the process by which the body absorbs it is lengthy and dependent on the availability of IF." And then they ignore that and say that it can be absorbed passively.
But try it for yourself. You may not have PA, which means you can absorb it orally.
I wonder what other causes of B12 deficiency there are - my levels were pretty low (I think sub 200) when I was first diagnosed - I eat a pretty normal diet so can't have been something related to what I eat.
There are two main causes - a dietary deficiency and an absorption problem.
If you can rule out a dietary deficiency (if you eat meat/fish most days of the week) then it's almost certainly an absorption problem (unless you've had surgery on your stomach or small intestine).
Some drugs can inhibit absorption (PPIs or metformin) as can some diseases (crohn's and coeliac's are the most common) or infection with Helicobacter pylori in the stomach.
But the most common cause of an absorption problem is Pernicious Anaemia, where your immune system attacks certain cells in the stomach.
Hi , Clive. I have asked this question a few times now, if it is the case that the excess is excreted via your urine, why does it shows still such a high level in your blood-test. Is it because everyone is different in how quickly the excess is getting rid off, that many people take a long time to excrete this excess and if so can that cause symptoms that mimick deficiency symptoms. Has any research been done to explain this question? I know it says it’s not harmful to have that excess in your body but still...... Can it be like with other medication that first seems to make you feel better ( for instance Triptans for migraine) then actually after a while as a rebound effect cause you to feel ill?
Sorry ACritical as a non medically trained person I am unable to answer your questions about rates of excretion or its safety.
Prior to my supplementing my three weekly injections with the B12 spray my wife used to "notice" that I grew pallid and more breathless in the run up to the injection. She has stopped noticing my symptoms sine I've used the spray.
The last serum B12 test I had taken on 29th October 2018 showed a level of 1830 pg/mL - this a couple of years after using the spray every day - and after an injection on 8th October 2018.
This may suggest that the high level was as a result of the spray and not the injection.
Thank you Clive. I tried sprays, they give me migraines as they have ascorbic acid in as preservative, going through my digestive system which triggers the migraine. I am self injecting now and do it when I feel it’s needed.
Hi I can completely relate to you. I had the loading doses Oct 19 and was back to normal. Then when I needed a blood test 6 months later during lockdown the doctors told me to come back a month later . I had a blood test at end of April and my results were so high compared to the October 137 Oct 394 April they told me to go away. I was so poorly with all the symptoms worse than ever , having been 7 months since last b13 injection. I persuaded a triage doctor I really needed it and he secured an injection every 3 months for me. However I got worse within a week tiredness being the worse. I took my self to a private doctor who ripped up my blood results . He said what you said that results don’t reflect the symptoms. I had 4 doses one a week and the nhs one and I’m back to normal . I now have one injection a month for £25 a month which is wonderful to feel normal again.
He said you can’t overdose and I take b12 supplements as well. Before I went on holiday he gave me a double dose to keep me going for 6 weeks.
I would take the oral spray as I have 2000mg supplements a day and injection once a month and I feel human again
This is super interesting Spottycupcake, thanks for sharing. I've been considering going down the private route, as I just don't have any faith that my GP really knows what he's talking about in this situation. I'd really like to find a specialist who actually has some expertise in B12 deficiency.
I went the private way like you did when some condescending GP put my monthly injection to 1 in 3 month. A double dose won’t do much more then the one. Your body can only deal with so much in one day. Perhaps doing a loading regime a week before travelling might be more beneficial. I now self inject and that way I am in control by injecting when I need . The price for private injection is about right , mine was £20 , obviously gone up since then.
I have used that spray in desperation when my NHS injection felt a lifetime away, but sadly it did nothing at all for me.
There is no recorded instance of a B12 "overdose" as far as I'm aware. The NHS give frequencies of 2 injections per week in certain cases, where function at cell level is a problem. They would not do this if it was proven to cause harm.
Don't forget that serum B12 test is measuring both active and inactive B12.
I would imagine that my serum B12 level , although not measured since 2016, remains at over 2000 ng/L. I'm still alive and feeling far better than I did when it was below 200 ng/L !
Hope you had folate, ferritin and vitamin D tested: these are the most obviously affected alongside B12 deficiency. Ask for a printout and look for low-within-range as well as below range: signs of struggle can get missed. Any of these could make you feel awful too.
All of this can cause thyroid problems, so have that checked as well when the opportunity arises. I know it's difficult at the moment, in many areas, to get bloods done if not seen as urgent.
If the frequency given is not adequate in controlling your symptoms, this will need addressing at some point. Please don't allow yourself to deteriorate just in order to demonstrate anything to your GP. Getting back can prove difficult.
Hi Cheryl, thanks for the reply. That's really interesting - I've had Folate (which was bang in the normal range) but not Ferritin or Vit D.
I think I'll continue to take the spray and monitor my symptoms - I might see if I can book a private appointment with a specialist as well, as I'd love to get a real expert opinion on what I should be doing. Just seems so crazy that the NHS are so unknowledgeable on the subject!
Not sure that you are going to find an expert that easily, Probein. They are hiding in the mos unlikely places and are as likely to be working somewhere within the NHS:
I have met a neurologist who told me he didn't know much about B12, a couple of heamatologists who told me that B12 was toxic, carcinogenic and highly addictive
- and an ENT consultant who knew exactly what a classic case of B12 deficiency looked like just by looking at my tongue and throat -without having to test 5 tubes of blood first -AND he'd read my GP's detailed report !
He encouraged me to continue frequent self injections and told me to be persistent because it would take a very long time. He wasn't wrong.
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