Breast cancer is the most common non–skin cancer and the second-leading cause of death from cancer among women, with an estimated 276 000 new cases diagnosed each year in the US.1 Breast cancer screening leads to early detection, but does not prevent the development, of breast cancer. Several medications are effective at reducing breast cancer incidence. For instance, randomized trials have shown that taking tamoxifen for 5 years reduces breast cancer risk for 20 years, but the adverse effects stop after the medication is stopped.2 Despite this, use of medications for primary prevention of breast cancer has been low.3 Reasons for low uptake include women’s low perceived need for preventive therapy and their concerns about the harms of treatment.3 This article provides an overview of the risks and benefits of medications for breast cancer risk reduction to promote their appropriate use.