I don't understand. You've shared a bunch of random pubmed links, but you have decided to ignore all the research about pharmacology in stuttering. There's no need to reinvent the wheel. Read the research on pubmed and then come back to this post. Here's a review for you to start: [https://pmc.ncbi.nlm.nih.gov/articles/PMC7118465/](https://pmc.ncbi.nlm.nih.gov/articles/PMC7118465/)