Do you stutter when you are alone? I don't and never have. If it was a parasite or some external factor we would stutter all the time. Stuttering to me is a state of mind. Although what I am going to try and do is add some more vitamin B vitamins as well as calcium and magnesium as they are calming and stress reducing vitamins and minerals. I notice that the less I care about stuttering the less I stutter, it is all state of mind. If you dont give a crap about what people think and just say what you need to say you will stutter less and less