They work systemically , so a hormone, such as estrogen , made and released by the ovaries , can effect the breast, uterus , bones, and many other organs. The major SERM being used today is tamoxifen .
Tamoxifen has a few important side effects .
Some women experience hot flashes and vaginal dryness while taking tamoxifen. These side effects are due to tamoxifen's role in blocking estrogen from affecting the different cells in the body. Thus just as it prevents estrogen from causing cancer cells to multiply, tamoxifen also prevents estrogen from maintaining some women's natural lubrication. These side effects can be managed, though. Your doctors will discus these symptoms and what you can do to manage them if hormone therapy is a treatment option.