@BeAware Because sadly the brain and what the meds are actually effecting are not an exact science. To be honest, I'm pretty sure most of are less of we know why this does this to more of "oh hey, on a lot of people it seems to cause this reaction....we have no clue why" This unfortunately can make it absolutely maddening to find one that actually works for you. But it's also a complete misunderstanding, most of the of those that need it for ADHD it reacts differently in their brains anyway.