I don't necessarily mean the most effective long-term or anything like that.  I mean that when you started taking it, you realized how messed up you were without it.  


For me it would be Clozapine.  I had no idea how many voices were talking in my head all of the time until they were gone.  I also didn't realize how often I was getting mixed episodes - you know, the ones where you have immense amounts of energy, perhaps a bit hypersexual... but you also have bugs crawling up and down your arms and you want to rip your skin off and the voices in your head are getting darker and louder.  I started Clozapine, and all of that is just gone.  It is strange to think I thought all of that was on some spectrum of normal, but it was actually really messed up.  


What medication has made the most dramatic difference for you?