Supplements. Almost 2 months on 200mg b6 daily (first paper), a couple of weeks with added b2 (found the second paper). Effects kicked in in ~half a week. Contrary to the paper, the effects still mostly wear off in over a day. Tried both ritalin and non-stimulants before (which worked), but all had bad side effects. These vitamins are about as effective for the issues I had.

I didn't get tested first, so can't tell if I would come up with the described deficiencies from the second paper.