@Wisebaxter I felt a little dizzy for aproximatelly 5 hours, at first I doubted if it was from modafinil, as I have recently experienced quite often dizzyness caused by stress at work, but I took a half of the pill yesterday again and after a couple of minutes I experienced a light dizzyness and a little bit of tirednes( I think caused by dizzyness). I was perfectly fine driving thought. And about the positive effect: for sure not when I felt dizzy, maybe just in the evening, but even then I couldn’t say if I could concentrate more ? so strange