i have tried a number of medications for ADD... adderall when i get the dose timed out correctly works wonders... when my timing is off due to an irregular work schedule and different sleeping patterns.. it's hell. Talked to specialists they suggested that typically drugs have an 8 hour life., this one has 6... so if you take it at hour 5... you overlap and the up and down mood swings and changes won't happen. some days i hit it perfect and my work is drastically improved.. but havent' got the system down perfect. the side effect i've noticed.. vision issues. -- and yes.. if you take double by mistake or two -- too close together.. i have cried my eyes out for no apparent reason and then turned paranoid.. and wanted to just keep away from social things. something very unlike me.