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B12 dosage - sublingual versus transdermal

Sarah94

Senior Member
Messages
1,087
Location
UK
Hello,

Does anybody know how much of a sublingual B12 dosage the body typically absorbs?

According to Dr Myhill, only 1% of an oral B12 dose is absorbed, and around 6% of a transdermal dose. I've been having very good effects using a transdermal spray that I bought from Myhill's online shop - I've been having 10 mg of it daily (so if Myhill is correct about the absorption rate, then I'm absorbing 0.6 mg of B12 daily). Unfortunately this spray has gone out of stock and so I am probably going to have to switch to sublingual B12. But I don't know what the equivalent dosage would be when accounting for absorption rates.
 
Messages
99
Have you considered injections? The sublingual absorption rate was too low for me; I switched to self-injecting 1mg hydroxycobalamin every few days (0.33mg/day), and felt immediate relief.

Now that my stores have been refilled and my nerve tissue regrown, I've stretched out the time between shots to 1mg every five days or so (about 0.2mg/day). I'd like to get to one 1mg injection every three months.
 

Hip

Senior Member
Messages
17,824
According to Dr Myhill, only 1% of an oral B12 dose is absorbed, and around 6% of a transdermal dose.

I have not seen any studies on the bioavailability of sublingual B12 nor transdermal B12, though there have been studies on B12 intranasal absorption like this one, which found around 2% to 5% absorption in the nose.


If you want to ensure B12 is efficiently absorbed, you might consider Greg's B12 transdermal oils, which are estimated to pull around 80% of the B12 through the skin by means of permeation enhancers in the oil. So with these B12 oils, you get doses comparable to injections.
 

Mary

Moderator Resource
Messages
17,334
Location
Southern California
I did injections (3 x a week, 5000 mcg. each) of both methylcobalamin and hydroxocobalamin (at different times) for a couple of years and noticed no difference. I then tried daily sublingual tablets (2 x 5000 mcg. a day) and noticed no difference. I know I was too impatient and just couldn't/wouldn't wait the many minutes it took for them to dissolve.

Then I tried liquid sublingual methylcobalamin, two 5000 mcg. doses a day, and finally noticed a difference in energy. I think I absorb it much better than the tablets. I've used both Bluebonnet and Why Not Natural liquid methylcobalamin with good results - I get them from Amazon.

I haven't tried the transdermal products though have heard good things about them.