The effects of methylphenidate (0.3-0.4 mg/kg) cf placebo on sleep in 10 children with ADHD are reported in a double-blind crossover study at the Bnai Zion Medical Center and the Technion-Israel Institute of Technology, Haifa, Israel. Sleep duration was significantly shorter during the drug period compared to placebo or baseline periods. The percent of quiet sleep was lower in the ADHD study group compared with controls in baseline measures, but not during methylphenidate treatment. 
COMMENT. Children with ADHD have significantly prolonged sleep duration and a trend toward a lower percentage of quiet sleep, possibly attributed to hypoarousal or fatigue. Normalization of sleep patterns and decreased sleep duration achieved by methylphenidate could result from increased arousal. Insomnia, frequently reported as a side effect of methylphenidate, requires closer study.
Perceptions of methylphenidate effects on peer interactions of ADHD children were studied by psychologists at the University of California, Los Angeles and Irvine . Analyses of observations of videotapes by 96 undergraduates showed that medication increased social withdrawal and dysphoria/disengagement, suggesting negative interpersonal consequences of these unintended internalizing behavior changes, even when not cued by rating scales. A positive medication effect was obtained in the category of leader/planner, behaviors requiring social organization and foresight.