NOLVADEX 20

Tamoxifen is a selective estrogen receptor modulator (SERM) widely used in the treatment and prevention of estrogen receptor-positive (ER+) breast cancer. It exerts its therapeutic effect by competitively binding to estrogen receptors, primarily in breast tissue, thereby inhibiting the proliferative actions of endogenous estrogens. Tamoxifen acts as an estrogen antagonist in breast tissue but exhibits partial agonist activity in other tissues such as bone, endometrium, and liver. It is administered orally and typically used in both adjuvant and metastatic settings, as well as in high-risk individuals for chemoprevention. Tamoxifen has been shown to significantly reduce recurrence and mortality rates in ER+ breast cancer. Common side effects include hot flashes, menstrual irregularities, nausea, and fatigue. Long-term use may increase the risk of endometrial carcinoma and thromboembolic events, necessitating periodic gynecologic and cardiovascular monitoring.