hi. my brother is exactly the same, he also talks and interupts all the time, and i guess we are pretty hard on him sometimes, but i always tell him that i'm not yelling because i'm mad, but because it's not ok to interupt when other people are talking and we also make sure to tell him we love him..  I also notice that my brother is much more extreme when he's eaten anything containing sugar.. perhaps your son is eating too much sugar or, he's eating sweets behind your back? I remember doing that when I was a kid, since having adhd my brain got so tired so I craved a lot of sweets. and I've also heard that apples makes kids extra hyperactive.. anyways physical activity is still the best way to get all that energy out:)