Is he in therapy with a good psychologist? Pills alone won't help. Also the hitting himself in the head reminds me of autism, high functioning.
Whatever...he needs a very intensive evaluation, not just a prescription. And he needs a professional who knows how to do testing for all disorders. My son had ten hours of testing and we also had to fill out forms. A pain, but we got answers and he is now really doing well.
I love Neuro psychological testing. This is not a neurologist. It is a psycologist with additional training in the brain. You can find them in university and children's clinics. I can not express in words how thorough my son's doctor was. He worked at Mayo Clinic once and had a long waiting list. The good ones do, but they are worth it.
Good luck!
