Faslodex (fulvestrant) is an anti-estrogen medication. It works by blocking the actions of estrogen in the body. Certain types of breast cancer use estrogen to grow and multiply in the body.

Faslodex is used to treat some hormone-related breast cancer. Faslodex is also used in postmenopausal women whose breast cancer has progressed after treatment with other anti-estrogen medication.

Faslodex may also be used for purposes not listed in this medication guide.