Selective estrogen receptor modulators, or SERMs, are
medications that act similarly to estrogen in some tissues of
the body and block the effects of estrogen in others. The two
most common SERMs used in the United States are raloxifene
(i.e., Evista) and tamoxifen (i.e., Nolvadex). How does estrogen
affect the body? Estrogen is a female hormone. It is made by the
ovaries from puberty to menopause. It acts on many different
cells in the body such as the brain,the breasts, the bones, the
heart and the uterus. Estrogen is sometimes given to women after
menopause to deal with the symptoms she may get from the normal
decline in these hormone levels. However, estrogen can cause
tissue growth in a woman's breast and uterine lining. If used
for more than 5 to 10 years, it may slightly increase the risk
of breast cancer. It may also slightly increase the risk for
uterine cancer in some women. Women who take estrogen and do not
have their uterus are not at risk for uterine cancer. Women who
still have their uterus and