This may come off as kind of rude, so I apologize in advance if it comes off that way. I feel like a more constructive direction you may want to consider is taking more responsibility for helping yourself rather than relying on doctors or medication to help you. I've been where I think you are now & it wasn't until I started figuring out how I could help myself that I started improving. I tried speech therapy as a kid & tried all these different "cures" (like thiamine or B12), but nothing ever produced any results. It wasn't until I started putting myself in uncomfortable situations, & often embarrassing myself, that I started to stutter less. Start small. Like really small. Like ordering something you know you'll stutter severely on or answering the phone. Next do something that stresses you out a little bit more like talking to a cute girl or saying something (anything) in front of a group of people. If you keep on a consistent track, eventually that first thing that stressed you out (answering the phone for example) isn't even remotely stressful anymore because you've done way scarier things & lived to tell the tale. I'm 30 now & have been doing this since my mid teens. I've progressed so much to the point that I'm now a drill sergeant in the United States Air Force & can speak comfortably (& yell haha) in front of a group of 400 people that I don't know, still stuttering to various degrees depending on the day mind you. If I had stayed in the mindset of looking for someone else to cure me, there's no way in hell I would be where I am today in regards to how I live my life with a stutter.