Is one type of b12 better than another?

[CW12]

I am now self injecting and my amazing new (to me)Dr asked what type of b12 I want. I was having cyancobolomin so that is what I went with. Any suggestions?

[wedgewood]

Cynocobalamin was the injectable B12 of choice here in the U.K. . Now it’s Hydroxocobalamin. , which is reputed to stay in the system longer than Cynocobalamin. I have tried Methylcobalamin , and found it no better . It’s also much more expensive ( which wouldn’t matter if it were better ) Its more volatile and unstable than Hydroxocobalamin and Cynocobalamin.

I use Hydroxocobalamin. , which is what is prescribed here in the U.K.

[fbirder]

Once they enter the cell all forms of B12 are converted to cob(II)alamin. They are, from that point on, functionally identical.

Before they enter the cell there will be some differences in distribution and elimination. That explains why cyanocobalamin requires more frequent administration than hydroxocobalamin.

Many web sites will tell you that methylcobalamin is the only type that works. That is wrong - b12science.com/B12Science/D...

I would stick with the cyanocobalamin if you're not in the UK. Hydroxocobalamin if you are.

[CW12 in reply to fbirder]

Just curious why cyanocobalamin for USA and hydro for the U.K.

I’m currently injecting with cyan and was thinking of switching because the hydroxocobalamin is what so many on this forum ( from U.K.)use. It seems to last longer.

I am currently injecting once a week. I have seen multiple posts about the safety which is reassuring. I am a nervous person and always want to take the safest choice .

[fbirder in reply to CW12]

If you don't have Leber's (something) then cyano should be fine. And you would know if you had Leber's (something).

No idea why the US don't use OH but CN.

If CN is easier to get then I would recommend trying that to see if it allows you to still use a sensible regimen.

[Retteacher]

In a major study of the beneficial effects of B12 supplements in reducing the risks of further ischemic strokes in patients who had had one, the authors had to exclude patients who had kidney problems. They state that in such excluded patients, cyanocobalamin has been shown to cause some toxic symptoms because it has not been excreted normally. This is the first time my husband has found anyone talking about toxic effects from B12 supplements. They then go on to say that it is not known if the same thing applies to the other forms of cobalamin supplements. This suggests that you might be better to use the hydoxycobalamin injections as used in the UK but that is only a suggestion - further research required.

[fbirder in reply to Retteacher]

It seems that it is aluminium in some cyanocobalamin preparations that cause the problems in those with renal impairment - drugs.com/disease-interacti...

That sounds more like a problem with oral cyanocobalamin as I've not encountered Al being used in injectable cyanocobalamin.

Edit: Just found a preparation that does contain aluminium - dailymed.nlm.nih.gov/dailym...

[helvella in reply to fbirder]

But even that only contains 0.2 micrograms per mL (or less). Which suggests it only exists as an impurity (e.g. some aluminium item used in making it).

Further, even the warning only starts at twenty times that (other than the "Tissue loading").

Research indicates that patients with impaired kidney function, including premature neonates, who receive parenteral levels of aluminum at greater than 4 to 5 mcg/kg/day accumulate aluminum at levels associated with central nervous system and bone toxicity. Tissue loading may occur at even lower rates of administration.

PS: Actually contains aluminum rather than aluminium.

[fbirder in reply to helvella]

Ah! I remember this from a few years back. It's a consequence of the anti-vaxxer paranoia in the USA and their lunatic safety labelling.

In actuality the stuff probably contains close to zero aluminium. But they cannot say that. Because you cannot prove that something contains zero aluminium, besides everything will contain some aluminium (it is, after all, the third most common element in the Earth's crust after oxygen and silicon).

So they run a test looking for aluminium. And that test has a lower limit of detection of 200 mcg/L. So they aren't allowed to say it contains no aluminium, only that each ampoule contains less than 0.2 mcg.

But, because they cannot say it contains zero aluminum, they have to include the 'This product contains aluminum' warning.

You get similar stuff in California especially. Their laws regarding labelling of potential carcinogens is equally ridiculous. So much so that the Disney corp. have to warn people that Disneyland may contain carcinogenic materials - abc.net.au/news/2019-06-04/...