Spotlight on Atomoxetine in Adults with Attention-Deficit Hyperactivity Disorder

Dene Simpson, Greg L. Plosker

Atomoxetine (Strattera) is a selective noradrenaline (norepinephrine) reuptake inhibitor and nonstimulant that has shown greater efficacy than placebo in attention-deficit hyperactivity disorder (ADHD) in adults. In two large, well controlled, 10-week trials in adults with ADHD, improvements in ADHD symptoms, as assessed by investigator- and patient-rated scores, were greater with oral atomoxetine (60, 90 or 120 mg/day) than with placebo. Mean reductions in the total ADHD symptom score on the investigator-rated Conners' Adult ADHD Rating Scale (CAARS) in atomoxetine versus placebo recipients were 28.3% versus 18.1% and 30.1% versus 19.6%, respectively. Mean reductions in the scores on the Clinician Global Impression of Severity Scale, patient-rated CAARS and Wender-Reimherr Adult Attention Deficit Disorder Scale were also significantly greater with atomoxetine than with placebo. Continued efficacy was demonstrated in a noncomparative, 34-week extension phase. Atomoxetine was generally well tolerated in clinical trials; withdrawal rates due to adverse events in atomoxetine- versus placebo-treated patients participating in the two major trials were 7.8% versus 4.3% and 9.3% versus 2.4% (p < 0.05 for the latter trial). Adverse events reported significantly more frequently with atomoxetine than placebo included dry mouth, insomnia, nausea, decreased appetite, constipation, dizziness, sweating, dysuria, sexual problems and palpitations. Modest increases in heart rate and blood pressure were well tolerated and gradually decreased on cessation of treatment. Atomoxetine was not associated with QT interval prolongation. Atomoxetine can be administered once or twice daily. Its subjective-effects profile is different to that of methylphenidate and atomoxetine is not associated with abuse or diversion; it is therefore not a controlled substance in the US. This also means repeat prescriptions during long-term treatment can be more conveniently processed.