A pilot study of atomoxetine in young children with attention-deficit/hyperactivity disorder.

OBJECTIVE The purpose of this study was to assess the effectiveness and tolerability of atomoxetine during acute treatment of attention-deficit/hyperactivity disorder (ADHD) in 5 and 6 year olds. METHOD Twenty two children (male n = 19, 86%) with ADHD were treated with atomoxetine for 8 weeks in a three-site, open-label pilot study. Dosing was flexible, with titration to a maximum of 1.8 mg/kg per day. Parent education on behavior management was provided as part of each pharmacotherapy visit. RESULTS Subjects demonstrated a mean decrease of 20.68 points (SD = 12.80, p < 0.001)) on the ADHD Rating Scale-IV (ADHD-IV-RS) total score, 10.18 (SD = 7.48, p < 0.001) on the inattentive subscale and 10.50 (SD = 7.04, p < 0.001) on the hyperactive/impulsive subscale. Clinical Global Impression-Severity (CGI-S) was improved in 82% of the children (95% CI, 66-98%) and Children's Global Assessment (CGAS) scores improved 18.91 points on average (SD = 12.20, p < 0.001). The mean final dose of atomoxetine was 1.25 mg/kg per day (SD = 0.35 mg/kg per day). Mood lability was the most commonly reported adverse event (n = 12, 54.5%). Eleven subjects (50%) reported decreased appetite and a mean weight loss of 1.04 kg (SD = 0.80 kg) (p < 0.001) was observed for the group. Vital sign changes were mild and not clinically significant. There were no discontinuations due to adverse events or lack of efficacy. CONCLUSION Atomoxetine was generally effective for reducing core ADHD symptoms in the 5 and 6 year olds in this open-label study.