It doesn't seem that this was mentioned yet. World-renowned mycologist Paul Stamets had his stutter cured from magic mushrooms. Watch here: https://www.youtube.com/watch?v=DAR4yH6TbtA
This is incredible, I definitely believe it's possible with psychedelics. I've stuttered all my life and have accepted it as part of my life, but I think I'm going to try it. Definitely not taking an ounce at one time though!