"my son is 14 and has always been super sensitive to these meds- he was diagnosed at 6 adhd. we started with concerta- he lost 11 lbs in 5 weeks. we switched to a slow release methylphenidate.  at christmas, it was felt that maybe he needed something different- his last increase didn&#039;t seem to be helping. that&#039;s when we started vyvanse. i have seriously mixed feelings about this drug. there is some control of the hyperactivity component but he&#039;s grouchier, more argumentative and not really more productive. is it age and adolescence?"