The general finding was that long-term (2 years) atomoxetine treatment was generally well-tolerated and effective in the treatment of young children with ADHD. Effectiveness was demonstrated by total scores and total T scores on the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version. Over the 2-year period, 25.7 percent of the children discontinued using atomoxetine because of no showing of improvement; adverse effects were clinically minor and transient; and only 4.0 percent of the children discontinued the drug's use because of an adverse event. There were statistically significant increases in pulse and blood pressure, along with decreases in cardiac pulse-rate interval, but none of these changes were deemed both statistically significant and clinically threatening when measured by laboratory tests and electrocardiogram exams. Increases in height and weight occurred, but growth rate slowed over the 2 years. The data was pooled from 6- and 7-year-olds (n=272) who met DSM-IV criteria for ADHD and who were enrolled in clinical trials of atomoxetine treatment for at least 2 years. Atomoxetine is a potent inhibitor of the presynaptic norepinephrine transporter with minimal affinity for noradrenergic receptors or for other neurotransmitter transporters or receptors. 4 tables, 1 figure, and 42 references