What is Tamoxifen and What are its Benefits?

— -- Question:What is tamoxifen and what are its benefits?

Answer: Tamoxifen is a hormonal treatment for breast cancer that can reduce the risk of the cancer recurring by up to one-third and can reduce the risk of dying from breast cancer by as much as 25 percent. Tamoxifen is a pill; you take it once a day for up to five years. It works by blocking the ability of breast cancer cells to combine with the female hormone estrogen. This blockage results in the breast cancer cells no longer being able to divide.

Tamoxifen belongs to the group of drugs called SERMs, selective estrogen receptor modulators. Although it's an anti-estrogen to breast cancer cells, it has estrogen-like properties to bone, to the uterus, and other organs in the body. To bone, these estrogen-like properties are a benefit; it does not increase the risk of bone fracture. But on the uterus, tamoxifen used for five years can indeed increase the risk of developing cancer of the uterus by about 1 percent.

Next: Does tamoxifen become less effective over time?

Previous: What is hormonal therapy?