CYP2C19 and CYP2D6 genotyping in a cohort of patients with treatment-resistant depression

Introduction The prevalence of treatment-resistant depression (TRD) can only be estimated, but it can be assumed that about 25% of the initial treatment group meet the criteria for TRD (1). Since genetic polymorphisms of the corresponding genes of cytochrome P450 (CYP) isoenzymes CYP2C19 and CYP2D6 have been shown to influence the tolerability and efficacy and thus the therapeutic success of antidepressant pharmacotherapy (2), we aim to investigate the relationship between CYP polymorphisms and TRD in our study.