I also did not know you are not supposed to eat or drink anything for 6-8 hours before the test. Is there anything else I should know? My doctor did not tell me any of this. Neither did my neurologist.

The B12 should be stopped at least 3 days before any testing.

A week would even be better. If you do not, then the result will be artificially elevated from the supplement. All the ranges were made on volunteers who did not take any supplements.

All your test shows is that you are absorbing the B12 in your GI tract. So that shows you are taking it correctly.

If you are not using the methyl form, it may also reflect only cyano (which is inactive), and you will not know if this high level is working. If you take the methyl form, then the test level is reflecting the active form which is methyl.

Our doctors here didn't either.