I agree with the above. If I were you, I would take B12 absolutely alone and I would use 5000 mcg per day. And Jarrow is the one I have seen most confirmation of, but I'm sure there are other brands just as reliable.

And I would be very nice to my liver, as MrsD said. It could be another one of the many hoops B12 has to go through, but that would be my first thought too.

rose