Tamoxifen is a non-steroidal anti-estrogen. It binds to estrogen receptors to prevent attachment of estrogen molecules. In males, testosterone is converted by a process known as aromatization, so-called because of the activity of an enzyme named aromatase. Excess estrogen may cause gynnecomastia, water retention, and fat deposition. Tamoxifen can be used to control such side effects.It also improves the HDL (to LDL) cholesterol ratio, which is usually depressed when using steroids. Hope that helps |