selective estrogen-receptor modulator

selective estrogen-receptor modulator A designer estrogen that can have the ability to both block and stimulate the actions of estrogen, having different effects on different body tissues. For example, raloxifene (brand name: Evista) prevents bone loss and lowers serum cholesterol as estrogen does, but it has been used, like tamoxifen, to block the action of estrogen on breast cells and is given to prevent breast cancer in some high-risk populations. Abbreviated SERM. See also designer estrogen.