There's a YouTube video with Matice anhjamine and she tried CBD oil. I myself chose to not use any substances because they made me feel like a zombie. I am using diaphragmatic breathing, meditation and yoga to help with my stutter. Plus, I don't pay attention to my stutter. I focus in living. Once I stopped caring about my stutter, my confidence increased and my fluency improved. I still have blocks but I dont focus on it.