Antagonism of tamoxifen and antidepressants among women with breast cancer

Abstract

Tamoxifen is used as an adjuvant therapy to reduce breast cancer recurrence among women with estrogen receptor positive tumors. Antidepressants are also commonly used in such women, to treat depression or to manage hot flushes, a frequent tamoxifen secondary effect. Some antidepressants could potentially inhibit cytochrome P450 2D6, required to activate tamoxifen, interfering with its action. Although there is not a clear cut directive on the subject, it is nowadays recommended to treat women with antidepressants with the lower cytochrome P450 2D6 inhibition potential to avoid a possible antagonism that may reduce tamoxifen s prevention of breast cancer recurrence at least in some patients with CYP2D6 genetic variation. The recommended antidepressants are desvenlafaxine, milnacipran, venlafaxin, escitalopram and citalopram.