Atomoxetine, which is indicated for treatment of attention-deficit hyperactivity disorder (ADHD), is predominantly metabolized by genetically polymorphic cytochrome P450 2D6 (CYP2D6).
Ten out of 100 children treated for attention deficit hyperactivity disorder with standard doses of atomoxetine were selected by a neurologist for cytochrome P450 2D6 and cytochrome P450 2C19 genotyping, based on late response (>9 weeks) and adverse effects (gastrointestinal problems, sleeping disorders, malaise, inactivity, and mood instabilities).
To determine whether physicians can adequately titrate atomoxetine without knowing genotype status for hepatic cytochrome P450 2D6, we pooled data from two open-label studies of atomoxetine in children and adolescents with attention-deficit/hyperactivity disorder.