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.

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

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

Do not receive fulvestrant without telling your doctor if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

Before you receive fulvestrant, tell your doctor if you have liver disease, a bleeding or blood clotting disorder, thrombocytopenia (a low level of platelets in your blood), or if you are taking a blood thinner such as Coumadin.

Call your doctor for instructions if you miss an appointment for your fulvestrant injection.

You should not receive this medication if you are allergic to fulvestrant, or if you are pregnant.

If you have any of these other conditions, you may need a dose adjustment or special tests to safely receive this medication:

• liver disease;

• a bleeding or blood clotting disorder; or

• thrombocytopenia (a low level of platelets in the blood).

FDA pregnancy category D. Fulvestrant can cause harm to an unborn baby or cause birth defects. Do not receive fulvestrant without telling your doctor if you are pregnant. Use an effective form of birth control, and tell your doctor if you become pregnant during treatment.

It is not known whether fulvestrant passes into breast milk or if it could harm a nursing baby. Do not receive this medication without telling your doctor if you are breast-feeding a baby.