A doctor recently ran a saliva test, to see why I suffer serious side effects to a large amount of meds. Surprisingly it identified a genetic defect where I don't metabolize b vitamins and started me on L-Methylfolate. Although I still hurt my pain is more tolerable on 75% or more of my time now. I also over metabolize other meds. It was a curious finding, one that can affect many health aspects. Does anyone else have or know about MTHFR gene defect?