The pharmacogenomic era: promise for personalizing attention deficit hyperactivity disorder therapy.

Attention deficit hyperactivity disorder (ADHD) treatment is often determined empirically through trial and error until an adequate response is obtained or side effects occur. ADHD is highly heritable and individuals experience wide individual variability in response to ADHD medications, suggesting that the mechanism of action of stimulant medications may provide clues for genetic predictors of response. The promise of ADHD pharmacogenetics is far-reaching and includes the potential to develop individualized medication regimens that improve symptom response, decrease risk for side effects, improve long-term tolerability, and thus contribute to long-term treatment compliance and improved effectiveness. Early ADHD pharmacogenetic studies have focused predominantly on catecholamine pathway genes and response to methylphenidate. Future efforts will also examine a wider range of stimulant and nonstimulant medications on a range of outcome measures and durations. Based on these studies, the potential for personalizing ADHD treatment in clinical practice will be determined.