An 11-year-old boy with attention deficit hyperactivity disorder (ADHD) who developed palpitations and unusual cardiac repolarization changes on the electrocardiogram (ECG) during standard dose treatment with atomoxetine is reported from Parkview Clinic and Birmingham Children's Hospital, Birmingham, UK. The boy had no history of cardiac or other medical problems. He was previously treated with Concerta and developed tics. Atomoxetine was substituted in a dose of 40 mg (1.1 mg/kg/day). After 10 months treatment, he developed sensations of fluttering in his chest and pallor, with increasing frequency, about 3 times a week, in episodes lasting about 10 min each. These symptoms were not associated with exertion. The ECG showed sinus rhythm, with unusual repolarization changes after the T wave, and a QTc of 0.32 sec. Both symptoms and ECG abnormalities resolved after stopping the drug. The QTc when off the atomoxetine was 0.31 sec. An echocardiogram was normal. Although ECG testing is not mandatory during atomoxetine treatment for ADHD, further research is recommended to study long-term effects of atomoxetine on the cardiovascular system. [1]

COMMENT. Atomoxetine is a nonstimulant noradrenergic drug licensed for treatment of ADHD. In initial pediatric trials of atomoxetine, cardiovascular adverse events were rare, but in adult studies, palpitation was a significant side effect (3.7% vs 0.8%; p=0.037). This appears to be the first report of atomoxetine-induced ECG repolarization changes with palpitations in a child. Abnormal blood pressure elevation is noted occasionally wih atomoxetine in our own clinic, and has been reported by others. (Ped Neur Briefs 2005;19:48) [2]