Well, Celexia is an antidepressant and is usually used for depression. Risperdal, of course, is an anti-psychotic used for Bipolar. Guanfacine has multilple uses with anxiety and ADHD being the main ones. However, it "May not help attention (ADHD) as much as stimulants." It seems like he is mainly being treated for Bipolar and not ADHD. Oh, and the fact that Ritalin did not help you really has very little to do with him.
It is not unusual at all for kids with ADHD to become very frustrated, depressed, and to strike out. Especially, if it is undiagnosed and they are being treated like normal kids.
Who is prescribing the meds? Is it a pediatrician or a psychiatrist ? Because if it is a pediatrician, he may be out of his area of expertise in this case.
While it is possible to have both conditions, bipolar and ADHD, the odds would favor ADHD. But it certainly would be helpful to know which one. If you haven't done so read up more on ADHD - this link might be helpful.
http://www.help4adhd.org/en/about/what/WWK1
I really don't know much about working with Bipolar. I can help a lot with ADHD. If it does seem more like ADHD or if you wish more info on ADHD, please post back here or over here -
http://www.medhelp.org/forums/ADD---ADHD/show/175 where I am also the CL. Best wishes.