If you don't feel like your psychiatrist is helping you, find another one or ask if they can refer you to someone who may have an idea of what is going on with him. There are behavioral clinics at all major University medical schools, you might ask if one near you has a clinc that deals with difficult behavioral diagnostics.
Adderal is a stimulant for people who have trouble with attention. If attention was not his issue to begin with, I don't know why it ever helped him. If it did help him, maybe what you need is a full developmental evaluation and a very detailed nueropsychological evaluation to look at exactly how he processes information to see if atteniton is an issue. I would be looking at things like, how does he process language? Yes, I know you do not see any deficits, that does not mean that he may not have some big dips and big highs in his processing skill numbers. Extreem subtest scatter in one area of functioning can cause a child to have behavioral issues. For example, though he is intelegent, if there is a huge difference between his verbal ablity and his non verbal abilty, and they still average out to be above average IQ that person is going to be frustrated wtih many tasks, and though they perform better than most people, they still react to frustration with misbehavior.
This may have nothing to do with his issue, but if you have never looked at the numbers of the subtests for his IQ test (suggest either a WISC or Woodcock Cognative) a Full language evaluation (with evaluation insturments for expressive and recptive langaugage, word retrieval, etc) and so on, then you have not really explored what could be going on here, and you should look for a professional who will order this kind of assessment and then go over it in detail with you to explain what it all could mean.
If he is not in cognative behavioral therapy, get him in right now. It does nto matter what the diagnosis is, therapy is delivered based on behavior. As your psychiatrist for a referal.
I would suggest that you read a book called "The Myth of Layziness" by Dr. Mel Lavine. While it deals with kids who are having trouble in school, it also explains many issues that do not usually get picked up in a cursary psychological evaluation by a psychiatrist alone. "All Kinds of Minds" is another good choice.
I do not mean to sound like a downer, but if all the testing and evaluation do not point to an issue with development, there are individuals with purely psychiatric conditions that are very difficult to treat, in the personalty disorder category, who are very smart, have few deficits, who know right from wrong, but are not capable of applying it to themselves, even with treatment. Keep seeking profesional help, and redouble your efforts to find someone who will be highy accesseable to your son and who is not satisfied to say "I don't know."
M.