SERMs are drugs that selectively block or activate estrogen receptors depending on the tissue: they act as antagonists in breast tissue (blocking estrogen-driven tumor growth) and as agonists in bone and other tissues (preserving bone density).
In oncology, SERMs like tamoxifen and raloxifene are primarily used for the treatment and prevention of ER+ breast cancer. Key pharmacist roles include managing adverse effects (e.g., hot flashes, VTE risk), counseling on adherence, and monitoring for endometrial safety (tamoxifen) and venous thromboembolism.