Thanks postconcussion. I am in a similar boat like you. Sensitive to vitamins and supplements. Thought I took B6, B12, Folic acid, Biotin - sublingual for a long time. Didn't make any difference for my symptoms. Luckily my blood work comes out fine. Only Vitamin D was low last year and I corrected with D3 supplement (infact over corrected .

Thought I can try magnesium since I heard(?) it calms the nerves and helps with brain zaps. During withdrawal of Effexor, anti-depressants etc, some seems to have that brain zaps. I do get that some times though I quit amitryptiline long time ago. This Mg is sublingual and that is the only reason thinking about trying.

CDP Choline also seems to like doesn't mess up stomach like other nootropics. What a crazy medicine, supplement, therapy world and it is tiring?