I've been on it since August. I went all the way up to 450mg in the summer/fall and it had no effect on my crippling depression. Then I had ECT to bring me out of the depression. I was stable for awhile but started having short bouts of depression when I went back to work. So it was upped to 300mg last Friday. By Monday iwas feeling baseline again, but that also follows my normal cycle pattern, so I've got to give it another couple of weeks to find out if it keeps the depression at bay or at least keeps it mild.