Tamoxifen blocks the actions of estrogen, a female hormone. Certain types of breast cancer require estrogen to grow.
Tamoxifen is used to treat some types of breast cancer in men and women. It is also used to lower a woman's chance of developing breast cancer if she has a high risk (such as a family history of breast cancer).
Tamoxifen is used to treat breast cancer that has spread to other parts of the body (metastatic breast cancer), to treat breast cancer in certain patients after surgery and radiation therapy, and to reduce the chances of breast cancer in high-risk patients.
This medication can block the growth of breast cancer. It works by interfering with the effects of estrogen in the breast tissue.