Medication adherence to hormone therapy (HT) in breast cancer survivors is often suboptimal and is affected by a range of factors. Patients are usually prescribed different generic formulations of HT drugs and their impact on side effects and on adherence and persistence is poorly understood. This study aimed to explore women's lived experience of HT medication brand changes (generic substitution) and its impact on side effects, quality of life and medication-taking behaviors, as well as on adherence and persistence. Nine female breast cancer survivors who had previous experience of HT medication brand changes participated in the study. Individual, online, semi-structured interviews were conducted and analyzed using interpretative phenomenological analysis. The findings identified three superordinate themes and nine subordinate themes that influenced the lived experience of medication brand changes for these patients: (i) experiencing brand changes, (ii) responsiveness of health care providers and (iii) future expectations. Women reported negative physical and emotional experiences of brand changes, which is often compounded by healthcare professionals' lack of information and reassurances, disbelief in the worsening of side effects and inconsistent advice regarding generics. These have implications for women's self-efficacy for medication-taking behaviors, ability to manage side effects and HT adherence and persistence.
Keywords: breast cancer; generic drugs; hormone therapy; interpretative phenomenological analysis; medication adherence and persistence; side effects.