My husband and I adopted my nice and nephew 12 years ago. The girl has ben with us since birth. The Son has been off and on since birth until he turned 4yrs. Old the he came to live with us so he could start school. He has been definent toward me eversince he has lived with us and still is that way. It has gotton so bad that I have told my husband that I was going to leave if he didn't sind him somewhere. He has been on ADHD with aggression meds. He started taking the medicine in the forth grade andwe have been in counsling since the eight grade. I took him to the doctor to get him on the mds. Again but it didn't work. He and I have fought and fussed at each other and it is so bad I can't even asked him a simple question or tell nim something. It is and has been every day since he came to live with us. He is 17yrs. Old and it is awful. My husband and I are at the end of the rope. He is hateful to his sister then the next min. he is mean. We need some help!!

So what does the medical community say, what is possible treatments and mediation that you have not done.

What country is this, different programs in various places. Does your family go to group family counseling ?

A child is not like a dog, you can not just "get rid of him" when you adopted you accepted for better or for worst no matter serious illness or what.

On his 18th birthday you have no more responsibility for him if you don't want, and can kick him out. If you think telling him now that he will be on his own then, feel free. Tell him he needs a part time job this school year (I assume he's a senior) to start saving for it.
Many parents go through this. There is little to do but wait.

Was the child properly diagnosed in the first place? Throwing drugs at the problem rarely solves anything. You need to get to the root of the problem before you can move on. It sounds more like deep seated resentment and no drugs will help in that case. What is it the child thinks he wants to do or happen in his situation ?