Back in May / June, my B12 was tested and was double the top of range at 1800 n/mol. GP told me to stop supplementing for the time being.
I was surprised that it was this high after only as I’d only been supplementing since January having been quite low at 500. Taking one a day Thorne’s Stress formula which provides 100 mg B12 - not really excessive.
How long is it usual to wait before resuming supplementation?
Many thanks
100mg??? Or mcg? I guess you’d have to retest first to see where your levels are before making next steps.
mcg
Sorry 😉
That’s OK. If it was mg ie anted to know how you got hold of that!
Did the GP give any rational or scientific basis for stopping B12 supplementation - or was it solely the number being high? Such as high levels of B12 causing problems.
Can taking too many vitamin B12 and folic acid supplements hurt me?
Not usually. Naturally high levels of Vitamin B12 may indicate an underlying severe disease which should be investigated. Also no trial has ever shown the benefit of supplementing vitamins outside of deficiency syndromes.
labtestsonline.org.uk/tests...
(I think there can be an issue if someone takes too much folate/folic acid such as 5 milligrams every day. But that is digressing.)
Further, it is difficult to find a proper assessment of the protocol for testing B12 in those who are supplementing. I've seen some suggestions that there has to be an appreciable gap between last supplement and any test. But, like so many things, when you try to find any good information, it seems to disappear. Nonetheless, it seems quite reasonable that there should be some gap between take a supplementary dose of B12 and a blood test - the question appears to be how long.
Thank you for your detailed response.
To be honest, I was quite surprised at the way the whole matter was handled. The test was actually done in hospital as an inpatient when I was undergoing investigations for neurological problems. I wasn’t asked whether I was supplementing. Nor did the hospital actually give me the result. As I know that high B12 levels without supplementation are indicative of several conditions, I was surprised that this wasn’t followed up. The blood test was done the day after my usually daily dose.
A short while later, during a random conversation with the GP, she told me the result and suggested that I stop it as it was too high. I certainly wasn’t getting any adverse effects from the high level.
The eventual diagnosis from an excellent and very thorough neurologist was Vestibular Migraine. Very unpleasant but the head pain itself isn’t intolerable. The speech loss, dizziness, staggering about are the main features.
To digress, for the last three days I’ve been afflicted with what I believe to be Occipital Migraine with all the VM symptoms. It started in back of my neck and has hammered its way up the back of my head to my crown and into my face. I’m not a ‘wuss’ when it comes to pain, but this is something outside my experience. I’ve lain in bed and cried for three days and nights. I did wonder whether my B12 had dropped and was a factor. Many years ago, when I had episodic migraine, increasing levels of B12 did the trick. I’ve also found that levels of fatigue have increased since stopping supplementation.
You have my sympathies, I was diagnosed with VM by both a Neuro and ENT consultant last year. It's horrible. I was told it was rare but from my own research its likely very underdiagnosed and often labelled as something else.
Have they discussed starting you on a daily migraine preventative to get your symptoms under control? Just to say I get regular B12 jabs due to having PA and my levels exceed 2000 and no one seems concerned about it.
Thanks for your response SS
The neurologist started me on Amytriptaline 10 mg titrating up to 40 mg. I only got to 30 mg before I had to quit. I had extreme anxiety, irritability and was very aggressive. I couldn’t sleep and was ‘on the move’ day and night. I kept waiting for ‘relaxed and drowsy’ to kick in but it didn’t. Apparently this is a rare ‘Paradoxical Reaction’.
Was changed to Pregablin, assured that it would target anxiety (it’s licensed for GAD), neuropathic pain and act as a migraine prophylactic. After a month I was dizzy, anxious and nauseous and Clinical Pharmacist at surgery did a ‘switch’ to Gabapentin 300 mg td. Been on that for two weeks. No progress. I don’t think it’s an intended prophylactic for migraine although it does improve neuropathic pain (not yet!). Side effects aren’t great. No drowsiness as you’d expect but ‘stiff’, painful arms and legs
I’m going to give the Gabapentin another two weeks as I don’t want to be an impatient patient. Will then see neurologist again for advice.
I don’t do well on antidepressants generally. I find them stimulating and they tend to increase anxiety.
I’ve been reading one or two Migraine forums and have read a lot about Candersarten. It’s an anti hypertensive but has good results in Migraine Prophylaxis. Years ago when I had episodic migraine, I was prescribed Propranalol (Beta Blocker) with excellent results. Can’t take it now though as it interferes with thyroid meds in that it hinders conversion - hence its use in Thyroid Storm / hyperthyroidism.
Finding the right drugs is a nightmare.
I tried 5 different ones before settling on Venlafaxine, Sertraline, Nortriptyline, Amytriptyline, Propranolol and Candestarten. Had to stop all due to side effects. A lot of people on my migraine forum recommended Ven as its widely used in the USA for VM. For me it really felt like last chance saloon. I started of on a tiny dose and slowly increased.
I've been on Ven since January and its helped a lot and the dreaded side effects have been minimal. The normal protocol is to stay on meds for a year then gradually titrate off to see if symptoms return. Some however choose to stay on preventatives indefinitely. I agree its a minefield.
Interesting to hear that you’re tolerating Ven but not so many other SSRI and tricyclicals.
Were your side effects generally due to drowsiness? Or did you get any hyper anxiety symptoms?
May mention Ven to neurologist.
Thank you 😉
Propranolol massively affected my asthma and as I'm hyoo shouldn't have been prescribed anyway 😏. Amytriptyline and Nortriptyline made my heart race, gave me the shakes and increased headaches, Sertraline was just horrible all round and I found Candestarten ineffective and it dropped my BP too much.
I take the modified release version of Ven, its much gentler and as I said I started on a really small dose and gradually increased. I had a lot of visual symptoms with my VM, bright lights,movement and fast moving screens really affected me and Ven has been very good at reducing those.
Apart from some nausea in the early days I havent really noticed any significant side effects which surpised me. Best of all no migraines either 👍
helvella - it suddenly rang a bell that I had enquired some time ago as to how long should be left between supplementing B12 and testing and I was told by Medichecks that it should be 2 weeks.
I think helvella ’junked’ that in a previous post. Could be wrong.
Thanks, Delgor.
I obviously was wrong. Sorry 🙈
No - I might have done! Honestly can't remember.
But there are all sorts of issues. Sometimes it looks like a regular dose does raise serum levels. Then when we stop, they drop fairly fast. But I think this is something that has not been very well researched.
I'm curious.
When you were supplementing B12 what kind of B12 were you taking? Not all types of B12 supplement are equal :
perniciousanemia.org/b12/fo...
If you've been supplementing with folic acid how much were you taking? Have you ever supplemented with other forms of folate?
Regarding having high levels of B12 I remember reading many years ago that Bradley Wiggins (a very successful British cyclist) took enormous amounts of B12 before races and had levels of 8000. I'm going to assume the units of measurement were ng/L.
en.wikipedia.org/wiki/Bradl...
.
About 15 years ago I supplemented with a B Complex containing high dose B12 in the form of cyanocobalamin. The product I took also contained high dose folic acid. It didn't do me any good at all. I gave up the product as a waste of money.
A few years later I tried high dose methylcobalamin and methylfolate and they cured the spots I'd suffered from since puberty (about 40 years) and the eczema I'd suffered from for even longer.
.
As has been mentioned already, very high levels of B12 can be an indication of serious disease, although if it occurs as a result of supplementing then I doubt any doctor would investigate for other causes.
academic.oup.com/qjmed/arti...
.
Articles about levels of B12 :
perniciousanemia.org/b12/le...
HI HB
This was a Thorne’s Stress Formula. See image. I forgot to mention that my folate was 2 x over range too. That was also very puzzling as I’ve had to fight to keep Folate in double figures for years.
I just can’t understand how such a comparatively low dose of B12 gave me such a high serum blood result in such a short time.
I have wondered whether my B12 was ‘climbing’ anyway for other reasons and that the supplement just helped the increase
Are you comfortable with that B6? Seems to high.
It’s too high. Not supplementing now but when I restart will go onto another brand. Thorne’s Basic is lower B6 but has 400 mcg B12. Don’t want that much.
Will sort another.
I’ve been using Liposomal Vitamin B Complex Softgels - 9 Methylated B Vitamins for Easily Absorbed, Vitamin B6, Folate & Inositol, 10x Better Absorption, 90-Day Supply, 90 Softgels (Pack of 1) amzn.eu/d/gPFCMOo I think it’s one of the ones Jaydee1507 suggests.
I’ve not had a B12 blood test since starting it so can’t comment on effectiveness.
I have heard that B6 above 10mg can cause neurological problems, if taken for some time. Also, from my experience, methylcobalamin can lead to a high serum B12 levels. Mine went quite high with even a single dose of 750mcg, though having a deficiency. Also wondering if methylfolate could cause a high serum folate level.
B12 supplementation can generally help with neurological problems, even if the primary causes are somewhere else, so I think you can continue the B12 supplementation, but B6 should certainly be reduced.
The precise form of B6 seems to be important - not just the quantity! 
helvella - Vitamers of Vitamin B6
Some time ago, I mentioned that the form in which we take vitamin B6 is important. I think I linked to this paper:
helvella.blogspot.com/p/hel...
Wow, this is really new information for me and really helpful.
I have been taking a B-complex with pyridoxine 3mg, as I was advised to take a good B-complex along with my B12 shots, as I have a B12 deficiency.
Guess I will have to change my B-complex now...
Thank you. Very interesting. Years ago, Pyridoxine was routinely prescribed in large doses for PMS (to little effect in most cases). I see that it is still advocated by NICE for PMS in doses of 50 mg to 100 mg
It's not a problem if it's over-range. B12 is water-soluble, so excess is excreted.
Why does it keep going up then Gg? Surely most if it should go down the loo.
Because, I imagine, you haven't reached the top limit of your body's needs yet. It's what doesn't get used that is excreted, not what you take - if you see what I mean. Doesn't just got straight through you and out the other end. 🤣🤣🤣
To have a meaningful result of B12 in the body you need to be off any B12 supplements, B12 fortified foods, energy drinks and such for at least 4 months as it can stay circulating in blood for months and often the high level after supplementing doesn't mean it's in any way used in the cells. Unfortunately, even with seemingly high levels you could be deficient on the cellular level too. High levels are not dangerous in themselves but the question always should be what (other than supplementing) could cause them.
The other crucial piece of the B12 interpretation is the folate level because low folate also raises B12 levels as they work in concert. You always need both of them checked together.
B6 supplements in the B complex should not exceed 10 mg and it's the only B vitamin which can become toxic at prolonged use at high levels.
If you were supplementing because your B12 was low in the first place (you didn't give a range for your 500 result) and you have a diet including meat, dairy, eggs, the reason for the low B12/deficiency should be investigated as it indicates malabsorption issues. However, in such a case the oral supplementation is not going to be effective, especially with neurological involvement, and you should be having regular B12 injections.
If you ae on FB, the best source of information about B12 in my opinion is the Pernicious Anaemia/B12 Defficiency Support group which has a lot of scientific research to back up every piece of advice they give.
Hope this helps. Best of luck with your investigation.
Thank you very much for your detailed and helpful response 😉
Sorry to jump in, does Active B12 tell us if it’s been taken up at cellar level?
HealthStarDust,
Vitamin B12 is bound to two proteins - haptocorrin where Vit B12 can not be up-taken by the cells so remains inactive), and transcobalamin (aka holotranscobalamin or HoloCT) available to cells for use in the body.
Therefore, the ‘active Vit B12’ test is a measure of the amount available for use in the cells.
Thank you.
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