Pediatric patients often receive selective serotonin reuptake inhibitors (SSRIs), escitalopram, and citalopram (es/citalopram) for anxiety and depressive disorders. However, this population has fewer pharmacogenetic studies examining CYP2C19 metabolizer status and es/citalopram treatment outcomes.

The present study analyzed the data from 263 youth < 19 years of age with anxiety and/or depressive disorders who received escitalopram or citalopram and underwent routine clinical CYP2C19 genotyping. 

The study found that the slower CYP2C19 metabolizers experienced more untoward effects than faster metabolizers, including activation symptoms, and had more rapid weight gain. It also found that many slower metabolizers discontinued treatment with es/citalopram than normal metabolizers. Meanwhile, the study found that faster metabolizers responded more quickly to es/citalopram and trended toward less time spent in subsequent hospitalizations. 

These results emphasize a difference in treatment outcomes with es/citalopram treatment in youth with anxiety and/or depressive disorders while using standardized dosing strategies without consideration of CYP2C19 metabolizer status. 

Front. Pharmacol. 2019. https://doi.org/10.3389/fphar.2019.00099