B12 doseage: I've actually got a prescription... - Thyroid UK

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B12 doseage

matty220 profile image
28 Replies

I've actually got a prescription from my gp for B12 and non-constipating iron (which I had to specifically ask for!) However, when I opened the B12 it's 50mcg. Surely that is a very small dose per day? Any thoughts please x

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matty220
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matty220 profile image
matty220

BTW my B12 level was 284 (190 - 900 range)

shaws profile image
shawsAdministrator in reply to matty220

matty220

I have looked at Solgar and can only see they provide 1,000mcg and 5,000mcg methylcobalamin. If yours is 50mcg it is miniscule.

matty220 profile image
matty220 in reply to shaws

Is Solgar a good brand then and can it be bought online and if so where from?

shaws profile image
shawsAdministrator in reply to matty220

Yes, I've used the Amazon Affiliate link where Thyrioduk.org get a very small commission if we use it when order anything from Amazon.

I have just noticed that Solgar also now use 'nuggets' on the front of the bottle as well as the mcg

amazon.co.uk/?&tag=thuk...

shaws profile image
shawsAdministrator in reply to shaws

You can also get it from any pharmacist usually.

shaws profile image
shawsAdministrator

Does it say whether the B12 is 'cynocobalamin' or methylcobalamin?

matty220 profile image
matty220 in reply to shaws

unfortunately it's cyanocobalamin

shaws profile image
shawsAdministrator in reply to matty220

I don't think they know there is a difference.

matty220 profile image
matty220 in reply to shaws

Can you explain the difference between these please, and also there's hydroxocobalamin isn't there?

shaws profile image
shawsAdministrator in reply to matty220

This is an explanation of the difference:-

methylcobalamininfo.com/met...

hydroxocobalamin is B12 in injection form which is given to those with Pernicious Anaemia or people with a severe B12 deficiency

patient.info/medicine/hydro....

medicines.org.uk/EMC/medici...

SeasideSusie profile image
SeasideSusieRemembering

I take Solgar sublingual Methylcobalamin and it is 1000mcg so I would say that 50mcg is a low dose.

shaws profile image
shawsAdministrator in reply to SeasideSusie

Sorry I made a mistake by putting cyanocobalamin twice instead of methylcobalamin.

It is good it is the 'correct' B12. 1,000mcg of B12 is fine. Each tablet is 1,000mcg and Solgar, as far as I know only do 1,000 and 5,000mcg. You can always take 2 at a time till you build up a bit. You originally said it is 50mcg but it is 1,000 mcg.

humanbean profile image
humanbean in reply to shaws

Shaws, the original author of this post was matty220, not SeasideSusie. :)

shaws profile image
shawsAdministrator in reply to humanbean

Thanks humanbean. Obliged - no wonder I was confused and made everyone else confused too :)

in reply to shaws

My middle name is 'confused' lol x

matty220 profile image
matty220

Thanks for all your input. I had a feeling it was a tiny dose.

I think I'll end up just buying it myself. I wanted to try the nhs route first.

I mentioned to the doc about the methyl and the hydroxo but he said he prescribes this one - it's probably cheaper!!

helvella profile image
helvellaAdministratorThyroid UK

matty220 ,

The British National Formulary says this:

Apart from dietary deficiency, all other causes of vitamin B12 deficiency are attributable to malabsorption. There is little place for the use of low-dose vitamin B12 orally and none for vitamin B12 intrinsic factor complexes given by mouth. Vitamin B12 in larger oral doses of 1–2 mg daily [unlicensed] may be effective.

evidence.nhs.uk/formulary/b...

So, basically, they agree with you! It is a very small dose and can only suit people who simply do not have enough in their diets. Anyone who has deeper issues must use higher doses. Indeed, there is little to no point in B12 oral supplementation below 500 or 750 micrograms. It is only when a sufficiently large dose is taken that the B12 can enter the body by diffusion even when there are absorption issues (e.g. inadequate intrinsic factor).

in reply to helvella

Hi helvella,

My B12 was 527ng/L (187.0-883.0) last September. I am supplementing with 1000 micrograms, do you think I should take this level every day?also if and when optimal level is reached should the dose be lowered?

Also my serum folate level was 6.5ug/L ( 3.1- 20.5) should I be doing anything about this result please?

Thank you very much x

matty220 profile image
matty220

Thank you helvella. I wonder if I'd ever get a test to see if my intrinsic factor is ok - somehow I think not!

You need more than that. My b12 was 212 and I supplemented myself as my gp told me my b12 was fine. I use BetterYou b12 spray 4 times a day. It's 1200ug in 4 doses.

My b12 went from 212 to 501 in 12 weeks.

matty220 profile image
matty220 in reply to

Thank you, I'll look into that one. I'm sure 50mcg will be near as useless!

matty220 profile image
matty220 in reply to

How does ug compare to mcg?

in reply to matty220

I think it'd the same.

helvella profile image
helvellaAdministratorThyroid UK in reply to

It is the same.

The scientific shortform for "micro" is the Greek letter mu μ .

Few non-Greek typewriters or computers used to be able to handle that character so someone chose to substitute it with the Latin letter u.

The Latin letter u itself was confusing (did it mean, for example "unit"?). So in medicine it was decided to use mc.

Hence, we see:

μg = ug = mcg = microgram = millionth of a gram

All of which = confusion.

My recommendation? Always type microgram in full.

Bluedragon profile image
Bluedragon

Those tablets will only be of use if the reason you are low is dietary. Otherwise, a waste of time and money. If you have symptoms then the Dr should give the loading injections. Jarrow and Bluebonnet are better makes of methylcobalamin - and you let them dissolve under your tongue/lip, not swallow them to bypass stomach. Read Could it Be B12 by Sally pacholok and pop over to the pernicious anaemia forum on here where you'll get good advice too.

matty220 profile image
matty220

Thank you Bluedragon. He never asked about my diet and never mentioned it could be dietary.

greygoose profile image
greygoose in reply to matty220

Matty, he just has no idea. Doctors know nothing about nutrition, they Don't do it in med school. That is why he's prescribing a useless dose of a useless from of B12. He doesn't know the difference - and, as you said, it's cheaper - at 50 mcg they must be practically giving it away! lol

I would think, that with such a low level, you'd be better off taking 5000 for a couple of months. Optimal is 1000, and you can't over-dose on B12 because it's water-soluble. Better too much than too little. :)

matty220 profile image
matty220

Thank you greygoose. I'm fairly certain that's the route I'll take now.

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