Selective serotonin reuptake inhibitors have become the first-line antidepressant drugs because of their outstanding efficacy, high safety and good tolerance.3-6 Escitalopram oxalate is a highly selective 5-HT uptake inhibitor for the treatment of depression.7,8 Among them, escitalopram has a higher selectivity to 5-HT, can significantly alleviate depression and anxiety of patients, and is relatively safer. This evidence concerns the gene HTR5A and depressive disorder.