I'll use this post to thank everyone who has responded. I ordered 1mg jarrow mb12 so I can start slow and have a more equal ratio with preference toward the metafolin. We will see what happens. My symptoms are better now.. legs hurt though. I took 5 mg jarrow mb12 and 400mcg metafoliln.. so back to where I was with metafolin before I started. I will go slow at least starting with 1 mg mb12... also interesting info, rydra.. thank you. i have not had homocysteine checked in a long time. would be interesting to see where that is and I do take 200mg of p5p a day but I skip days and had probably skipped a week at some point during this quick ramp up..