At first I was very excited and was building the dose up very quickly (with a scedule made by my therapist) which caused me to speak almost fully fluently, but also caused my personality to change. At a bit lower dosis my fluency was pretty good. This effect lasted for about 14 months and when I quit them, my stutter was far worse. So I guess it helped pretty good while I took them. As for addiction, I think that as long as you have a professional, you won't get addicted. I had a therapist which I would email every week which was very helpful. If you don't have that I would say don't do any opiods as xanax, those can be very addictive. Hope this helps