Tamoxifen citrate is a type of hormone therapy called a selective estrogen receptor modulator (or SERM). It works by binding to estrogen receptors, blocking estrogen’s effects in some tissues while mimicking its effects in others. In breast tissue, tamoxifen citrate blocks estrogen from binding to its receptors, which may prevent the growth of cancer cells. Tamoxifen citrate mimics estrogen. Find patient medical information for Tamoxifen on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Tamoxifen is an antiestrogen drug used in the treatment of breast cancer. It blocks the activity of estrogen, helping to stop the growth of some tumors. Tamoxifen blocks the actions of estrogen and is used to treat and prevent some types of breast cancer. Learn about side effects, interactions and indications. Tamoxifen, sold under the brand name Nolvadex among others, is a selective estrogen receptor modulator used to prevent breast cancer in women and men. [15] It is also being studied for other types of cancer. [15] It has been used for Albright syndrome. [16] Tamoxifen is typically taken daily by mouth for five years for breast cancer. [16] Serious side effects include a small increased risk of. Tamoxifen and raloxifene have been shown to reduce the risk of breast cancer for some women. Learn more about these drugs and their possible side effects. Tamoxifen is used to treat breast cancer that has spread to other parts of the body in men and women. It is used to treat early breast cancer in women who have already been treated with surgery, radiation, and/or chemotherapy. It is used to reduce the risk of developing a more serious type of breast cancer in women who have had ductal carcinoma in situ (DCIS; a type of breast cancer that does. Tamoxifen (brand names: Nolvadex, Soltamox) is a medicine that blocks the effects of the hormone estrogen (called a selective estrogen receptor modulator, or SERM). Tamoxifen is a first choice among doctors for treating women who have not yet gone through menopause. The medicine can also be prescribed to women who have gone through menopause and to men. Learn about the side effects of tamoxifen, from common to rare, for consumers and healthcare professionals. Studies show that people receiving tamoxifen, a highly effective and commonly used therapy to treat breast cancer, face a 2- to 7-fold increased risk of developing uterine cancer within 2-5 years of tamoxifen treatment compared to the general population.