I have taken it before, (it's great for shedding a few unwanted pounds quickly) but don't remember any emotional/mental affects. However it seems that over the past week I've become very irritated at small things. I'm already in a fragile emotional state, and very stressed with school, work, and home. It's probably just a combination of those things. But I still wonder if the "legal speed" has a hand in it, too. It's definitely more caffeine than I'm used to.