Can't be taken orally?
There are sublingual tablets, yes. But I personally don’t get the same response from them that I do with the tablets.
Don’t try swallowing the pills. The problem is an absorbtion problem in the stomach and if it can’t be absorbed from food, it isn’t absorbed from a tablet either.
The myelin sheath also needs sufficient folate (i.e., folic acid) and an amino acid, methionine - as well as the Vitamin B12.
Also, in some recent studies, some elderly persons responded to ORAL supplementation with Vitamin B-12, of the non-sublingual type.
There are different types of Vitamin B-12, and some people say one should take the ‘methyl’ form, and NOT cyanocobalamin. The methylcobalamin version is not much more expensive — but I have NO idea if what I’ve read online is accurate, nor whether it’s ever been actually proven to be the superior form of B-12.
But for myelin health, both methionine & folate are also needed.