Pediatric anxiety disorders, including generalized anxiety disorder (GAD), are commonly treated with SSRIs; however, their efficacy and tolerability are challenging to predict. A recent study evaluated the efficacy and tolerability of escitalopram in adolescents with GAD and the effect of CYP2C19 phenotype on escitalopram pharmacokinetics.

It included patients treated with escitalopram (forced titration to 15 mg/day, then flexible titration to 20 mg/day) (mean age: 14.8±1.7 years) or placebo (mean age: 14.9±1.6 years) for eight weeks. It observed the outcomes as changes in the Pediatric Anxiety Rating Scale (PARS) score, Clinical Global Impressions (CGI) scales, vital signs, and adverse events. It also determined Plasma escitalopram and desmethylescitalopram AUC0-24 and CMAX and compared them across CYP2C19 phenotypes.

The study found escitalopram superior to placebo for baseline-to-endpoint change in PARS and CGI. It also described that increasing CYP2C19 metabolism was associated with decreases in escitalopram CMAX and AUC0-24. Vital signs, QTc, and adverse events were similar in escitalopram and placebo groups.

Thus, escitalopram can reduce anxiety symptoms, and the CYP2C19 phenotype influences the trajectory and magnitude of improvement. Variation in CYP2C19 metabolism causes significant differences in escitalopram pharmacokinetics; therefore, CYP2C19 phenotype should be considered when dosing escitalopram.

Source: J Clin Psychiatry. 2020 Aug 25;81(5):20m13396. doi: 10.4088/JCP.20m13396. PMID: 32857933; PMCID: PMC7504974.