Atomoxetine is a non-stimulant used for ADHD, and CYP2D6 polymorphisms influence its metabolism and thereby both its efficacy and its safety. CPIC published dosing recommendations by CYP2D6 genotype in 2019. This is about how much drug a person is exposed to at a given dose; it is not a prediction of whether ADHD treatment will help, and no genotype is used to decide whether to treat.
CPIC Guideline for CYP2D6 Genotype and Atomoxetine Therapy (Clin Pharmacol Ther 2019, PMID 30801677).
This page is educational and contains no dosing information. Where a clinical guideline covers one of these gene-drug pairs it is written for prescribers and works through validated algorithms alongside clinical monitoring. Nothing here is a reason to start, stop, or change a medication — that conversation belongs with the clinician or pharmacist managing your treatment.