I know most of the people will tell you that supplements don't work and they are probably right. But I have taken Magnesium and B6 and they helped a bit. I don't think they had a direct affect on my stammer but they reduced my anxiety hence making my speech more fluent. I also would like to shout out to the guy who recommended 5htp here a couple of weeks ago. It's great! However, I would really suggest you to keep your expectations low because they won't cure your stammer. Take them for a while, try different dosages but please don't exceed their recommended dosage. You'll might find a good combination after a while that can make your life easier.