Gender differences in the diagnosis of depression and anxiety, as well as in the use of psychotropic medication, remain a persistent feature of contemporary mental health systems. These patterns reflect broader structural inequalities that shape how distress is gendered expressed, interpreted, and managed in clinical settings. The medicalization of women’s experiences—historically framed through a biomedical lens that has tended to pathologize feminine life conditions—may contribute to the overdiagnosis and overprescription of mental health conditions among women. This chapter examines how diagnostic and prescribing practices emerging within clinical encounters may contribute to gender disparities in mental health across women’s life course. First, we introduce the concept of the medicalization of life, diagnostic cultures, and their relationship with gender and mental health. Then, drawing on diverse databases from the Spanish context, we analyze these dynamics through a life-course perspective, distinguishing between adolescents and young women, adults, and older women. The chapter concludes by discussing key findings and proposing actionable recommendations to reduce gender bias in mental healthcare.