autism
"My son became aggressive when he hit puberty (age 11), so the psychiatrist put him on this. For the first 2 months I was happy with the results.  But his aggression started increasing, and he became extremely aggressive over the next year.  His psychiatrist attributed it to rising male hormones and kept increasing the dosage, until my son was on 8 mg/day.  I finally had to have my son hospitalized, as he was a danger to me and others.  I was fed up, so I changed psychiatrists.  She prescribed Abilify, but it took weeks to wean my son off the Risperdal.  However, once he was off it, he became the lovely boy he used to be.  Every child is different, so keep that in mind!"