Product Details

Tamoxifen Citrate is an antagonist of the oestrogen receptor in the breast tissue via its active metabolite, 4-hydroxytamoxifen. In other tissues such as the endometrium, Tamoxifen Citrate behaves as an agonist, thus characterizing itself as a selective oestrogen-receptor modulator. Tamoxifen Citrate is the usual endocrine therapy for hormone receptor-positive breast cancer in pre-menopausal women, and is also a standard treatment in post-menopausal women although the aromatase inhibitors are frequently used in those cases. A few breast cancer cells require oestrogen to grow and the oestrogen binds to and activates the receptor in these cells. Tamoxifen Citrate is then metabolized into compounds that also bind to the oestrogen receptors but do not activate the same. Because of this competitive antagonism action, Tamoxifen Citrate prevents oestrogen from binding to its receptors blocking breast cancer cell growth.