Our son had a lot of aggression at that age. Turns out, he was severely constipated and in pain. As crazy as that sounds, his intermittent bowel pain led to his bouts of aggression (we were walking on eggshells, and the tiniest thing, and sometimes nothing, would set him off). If you haven't already done so, I would try to make sure he is having a good BM each day. We added probiotics, and TruFiber (a supplement that is tasteless and can be mixed in any drink). BTW, I would second the notion that looking into your child's unique biomedical profile can help immeasurably (MAPS physician is a place to start). At the time of the aggression for our son, his ammonia level was over 300 (like a severe alcoholic can get... this leads to lots of mental status issues). Just so you know, after fixing his bowels and ammonia, our son has had years of no aggressive episodes. Good luck, my heart is with you.

I can definitely relate. Sorry this may be a battle for a while. Have you tested your son for sub clinical seizures? They never picked up on my sons EEG.
My son is also very aggressive. He is 9 years old and getting bigger and bigger. He is now in a facility in LaCrosse WI. It isn't helping so I am awaiting his return as he is on a huge waiting list for a special needs school. I will NOT put him in the public schools!
That would be trouble. He was discharged from his last ABA school due to aggression .
Try your hardest to get your Psychiatrist to prescribe Depakote. I do believe it will help. My son went down 80% in those aggressive attacks after Depakote. The problem is that after a while you may have to tweak the meds. My son is also on Risperdahl for hallucinating. Right now the meds aren't working well and I am desperate so I know how you feel. I hate seeing him pound himself in the head and bite his leg due to what looks like extreme pain.
I am getting him in to see a Mayo Pediatric Neurologist.
I am desperate to get these seizures treated.

Let me know how it's going and I will be praying for your family.
This is so hard for the siblings but this will also strengthen all of you.
God placed this wonderful child with you for a reason.

God bless,

Nadine

Self-Injury in Autism May Be Sign of Pain

Click http://www.medpagetoday.com/Neurology/Autism/57944 for the full story:

We just started back with medication, again, too. Thanks for your reply

My son is so severe though he is verbal to a point. Communication is the big issue but the aggression and pain is out of control and is more than a communication issue. I have dodo been dealing with this for some time and not much is working. I did have a recommendation from Caren Haines who is a nurse . She is author if of the book Silently Seizing. This is s great book and hit home for me. I had to choose medication.