Hi Deb!
I had thought I had read the sublingual formulation was made for maximized absorption, esp. when anyone has GI absorption issues. I cannot tell you how much more is absorbed this way... exactly. If your methyl B-12 is a sublingual tab/lozenge, I would hope you will absorb a fair amount before it ever passes into your esophagus?
I wish I could find the resources I was reading the other day, as they were even putting forth the idea that the IM B-12 (injection) is less available to the body than a good sublingual? That's an interesting idea.

No worries... we will find the answers!

I hope you are feeling better!

~DejaVu