Here is info on B12 facts and for me, my B12 level comes in at about 2000 and I continue with 1000mcg AM and often one close to bedtime.... SO MANY doctors just don't know how much is good or not good etc...we have to be our own doctors so much and even go to support groups and hear other experiences. I've been doing this for a lot of years.

http://neurotalk.psychcentral.com/thread230120.html