Atomoxetine for the treatment of executive dysfunction in Parkinson's disease: a pilot open-label study.

Executive dysfunction (ED) is a prominent and often disabling feature of cognitive impairment in Parkinson's disease (PD). Few studies have examined treatments. Given the role of noradrenergic pathology in ED, atomoxetine, a norepinephrine reuptake inhibitor indicated for attention deficit hyperactivity disorder (ADHD), may be a potential treatment for PD-related ED. Twelve patients with PD and disabling ED completed an 8-week pilot open-label, flexible dose (25-100 mg/day) trial of atomoxetine. On primary outcome measures, atomoxetine was associated with improved ED based on the Clinical Global Impression-Change Scale (75% positive response rate; 95% CI: 43-95%, P < 05) and behavioral measures of ED [Frontal Systems Behavior Scale (FrSBE) Executive Dysfunction and Connors Adult ADHD Rating Scale (CAARS) inattention/memory subscales]. Adverse effects included sleep and gastrointestinal disturbances and hypomania. Atomoxetine is tolerable in PD and may benefit clinical manifestations of ED, warranting further study in controlled trials.