Clozapine placental passage at delivery: an update

Introduction Clozapine is an effective second-generation antipsychotic that is approved for treatment-resistant schizophrenia and risk reduction of recurrent suicidal behavior in schizophrenia or schizoaffective disorder. Its available pregnancy pharmacikinetics data remain limited, which presents a challenge for clinicians managing women taking clozapine during perinatal period . Objectives The aim of this study was to provide new data of clozapine and norclozapine placental passage and neonatal outcomes. Methods We retrospectively studied a consecutive case series of six pregnancies where there was clozapine exposure (5 in politherapy and 1 in monotherapy). Clozapine and norclozapine serum concentrations were determined in the mother-infant pairs on the day of delivery (intrapartum maternal blood and umbilical cord blood respectively) and measured using a validated high-performance liquid chromatography method. The within- and between-day precision expressed as the coefficient of variation (CV)% were both