I think the only thing we can say with some measure of confidence here is that you've been on and off a bunch of meds and drugs, and your stutter was affected - which is a pretty general association between a lot of stuff changing and the stutter also changing. It might be that the specific component here is something that eclitics even larger change in you in particular, and then also in your particular stutter. But nobody can know anything actionable from your situation. Please be careful with what kind of things you put into yourself.