I am a new member and for the life of me can not find much info on an over abundance of B12 in your system. I am currently being tested for everything due to fainting and convulsions. I had blood work done and my nurse called me stating my Dr says to stop taking B12. The problem is I don't take any supplements. My count is over 1,500 and I have no idea where it is coming from. I have constant headaches, dizziness, numbness in my limbs, fatigue. Only thing I could find is leukemia, hepatitis, or no such thing as too much B12. At a loss.