Not only are his behaviors likely being made worse by the Effexor, no drug that you add to the mix will make things better. Not Remeron (which is another antidepressant and will likely make things worse in the long run), not Depakote (or any of the mood stabilizers), not any of the antipsychotics. The only treatment that will reverse the adverse reaction to an antidepressant is stopping the antidepressant.
Further, antidepressants can cause a disorder known as antidepressant induced mania or bipolar. Discontinuation of the antidepressant is the first and maybe only step in treatment.
By the way, almost four years ago Wyeth issued this "Dear Health Care Professional" letter which warned specifically of suicidal ideation and hostility in children and adolescents taking Effexor. The letter flat out states "Effexor and Effexor XR have not been and are not now recommended for use in pediatric patients."
And finally, don't get too hung up on a placement being the "help" your child needs. There really isn't anything medically they can do in a placement that can't be done without a placement. Good medication management does not require placement but it does require doctors who can identify psychiatric adverse reactions to the medications they prescribe. Unfortunately, that isn't always the case.
