A Long Term Study of a Medication for Adults With Attention-Deficit/Hyperactivity Disorder (ADHD)

LYDO is a multi-center study that will enroll approximately 1925 adult outpatients with Attention Deficit/Hyperactivity Disorder (ADHD). Patients will receive, under open label conditions, atomoxetine up to 100 mg/day during the acute, open-label part of the study. Those patients that meet the response criteria will continue the blind phase of the study up to a year. During that period, patients that respond to atomoxetine will be randomized to continue the treatment with atomoxetine or with placebo (neither the patients nor investigators know if patients receive atomoxetine or placebo).