I realize that pyridoxine HCl (the most commonly available form of Vitamin B6 supplement) can be neurotoxic; however, pyridoxal-5'-phosphate (P5P) is the active form. Can P5P also be neurotoxic? Does anyone have any references indicating the neurotoxic potential of P5P? I have SFN and am considering taking P5P, but want to first make sure that there's no research out there pointing to its potentially being neurotoxic.