I've been on Adderall for about 2 years. Stuttered my whole life and diagnosed with ADHD at 38 (40yo now). I find that the Adderall helps my anxiety, which usually helps my stutter. With that said, there are situations where my heightened attention actually causes me to stutter more (focusing on my speech/what I'm going to say more). I'd say mixed feelings to its helpfulness. In all, it doesn't hurt very often. It helps more than hinders, but not significantly. As an aside, 20mg is pretty standard I think. I was on that for a while and just bumped up to 30mg recently. Hang in there- you're doing great, my friend.