This case describes a 43-year-old woman who developed amenorrhea after long-term treatment with escitalopram for anxiety, despite having no prior menstrual irregularities and normal prolactin levels. The case suggests escitalopram may contribute to menstrual disruption via increased ACTH rather than hyperprolactinemia. Clinicians should consider SSRI-related endocrine effects when evaluating unexplained amenorrhea. The gene discussed is PRL; the disease is amenorrhea.