Threshold, that is the type of addiction I had. I would NEED to use Welbutrin because I got to the point that I felt like I was literally dying if I went even a few hours without it! I would dread snorting it and knew the affect it would have on me...the first 15 minutes or so always left me feeling amazing, like I was flying and could conquer the world...minutes later I would be in hell again, a complete zombie who had trouble even speaking.