Generic name: fulvestrant (ful VES trant)
Brand name: Faslodex
Dosage forms: intramuscular solution (50 mg/mL)
Drug class: Estrogen receptor antagonists, Hormones / antineoplastics
Fulvestrant is used in postmenopausal women with hormone-related breast cancer that is advanced or has spread to other parts of the body (metastatic).
Fulvestrant is used alone or in combination with another medicine called ribociclib (Kisqali) to treat HR-positive, HER2-negative breast cancer in:
- women with no prior treatment; or
- women whose cancer has progressed after treatment with anti-estrogen medication.
Fulvestrant is used in combination with palbociclib (Ibrance) or abemaciclib (Verzenio) when the cancer has progressed after treatment with anti-estrogen medication.
Fulvestrant may also be used for purposes not listed in this medication guide.
You should not receive fulvestrant if you are pregnant.
Avoid getting pregnant or breastfeeding a baby for at least 1 year after you stop using fulvestrant.
Before taking this medicine
You should not be treated with fulvestrant if you are allergic to it, or if you are pregnant.
Tell your doctor if you have ever had:
- liver disease;
- bleeding problems; or
- thrombocytopenia (a low level of platelets in the blood).
You may need to have a negative pregnancy test 7 days before starting this treatment.
Fulvestrant may harm an unborn baby. Use effective birth control to prevent pregnancy while using this medicine and for at least 1 year after your last dose. Tell your doctor right away if you become pregnant during this time.
This medicine may affect fertility (ability to have children) in both men and women. However, it is important for women to use birth control to prevent pregnancy because fulvestrant can harm an unborn baby.
Do not breastfeed while using this medicine, and for at least 1 year after your last dose.
How is fulvestrant given?
Fulvestrant is given as two injections into a muscle of your buttock. A healthcare professional will give you this injection.
Each injection must be given slowly, and can take up to 2 minutes to complete.
Fulvestrant is usually given once every 2 weeks at first, and then once a month.
When treatment also includes taking abemaciclib or palbociclib, these medicines are taken by mouth and have daily dosing schedules. Also, palbociclib is taken with food while abemaciclib may be taken with or without food. Follow your doctor's dosing instructions very carefully.
Use all medications as directed and read all medication guides you receive. Do not change your dose or dosing schedule without your doctor's advice.
If you are a woman using fulvestrant with abemaciclib or palbociclib, tell your doctor if you are still going through menopause (you have symptoms such as irregular menstrual periods, hot flashes, night sweats, or vaginal dryness). You may need to be treated with an additional hormone medication.
What happens if I miss a dose?
Call your doctor for instructions if you miss an appointment for your fulvestrant injection.
What happens if I overdose?
Since this medication is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.
What should I avoid while receiving fulvestrant?
Follow your doctor's instructions about any restrictions on food, beverages, or activity.
Fulvestrant side effects
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
- signs of nerve damage--numbness, tingling, weakness, or burning pain in your buttocks, back, or leg.
Common side effects may include:
- pain where the medicine was injected;
- pain in your arms, legs, feet, or back;
- bone pain, joint pain, muscle pain;
- nausea, vomiting, loss of appetite;
- diarrhea, constipation;
- weakness, feeling tired;
- cough, feeling short of breath;
- hot flashes; or
- abnormal liver function tests.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect fulvestrant?
Tell your doctor about all your other medicines, especially:
- a blood thinner--warfarin, Coumadin, Jantoven.
This list is not complete. Other drugs may affect fulvestrant, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.