selective estrogen-receptor modulator

drug

Also known as: SERM

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Last updated

July 17, 2026

Quick Summary

Selective estrogen receptor modulators (SERMs) are a class of drugs that interact with estrogen receptors in the body. These drugs can act as agonists, enhancing estrogen activity in some tissues, or as antagonists, inhibiting estrogen activity in others. Examples of SERMs include tamoxifen and raloxifene.12

SERMs are used for various medical purposes. Tamoxifen, for instance, is primarily used in the prevention and treatment of breast cancer by inhibiting estrogen's growth-promoting effects on breast cells. Raloxifene is used to prevent and treat osteoporosis in postmenopausal women and can also help reduce cholesterol levels.32

The dual action of SERMs makes them beneficial in tissues where estrogen is helpful, such as bone, while blocking its potentially harmful effects in tissues like the breast and uterus.2

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antiestrogen
Selective estrogen-receptor modulators (SERMs), such as tamoxifen and raloxifene, produce estrogen action in those tissues (e.g., bone, brain, liver) where that action is beneficial and have either no effect or an antagonistic effect in tissues, such as the breast and uterus, where estrogen action may…
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Selective estrogen-receptor modulators (SERMs), such as tamoxifen and raloxifene, produce estrogen action in those tissues (e.g., bone, brain, liver) where that action is beneficial and have either no effect or an antagonistic effect in tissues, such as the breast and uterus, where estrogen action may…
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tamoxifen
…to its reclassification—from antiestrogen to selective estrogen receptor modulator (SERM). In 1978, following a series of successful clinical trials in humans, the U.S. Food and Drug Administration (FDA) approved tamoxifen for the treatment of metastatic estrogen receptor-positive breast cancer. In 1998 the FDA further approved the use of tamoxifen for…
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…to its reclassification—from antiestrogen to selective estrogen receptor modulator (SERM). In 1978, following a series of successful clinical trials in humans, the U.S. Food and Drug Administration (FDA) approved tamoxifen for the treatment of metastatic estrogen receptor-positive breast cancer. In 1998 the FDA further approved the use of tamoxifen for…
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