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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





Fulvestrant is used to treat breast cancer that has not responded well to other medications (e.g., anti-estrogen drugs such as tamoxifen). Breast cancer tumors grow when the cells are stimulated by the hormone, estrogen. This drug works by blocking the effect of estrogen on the breast cancer tumor cells.

How To Use

Learn all preparation and usage instructions in the product package. If any of the information is unclear, consult your doctor or pharmacist. Inject this medication slowly into a muscle (IM), preferably in the buttocks, usually once monthly; or use as directed by your doctor. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard needles and medical supplies safely. Consult your pharmacist.

Side Effects

Nausea, vomiting, diarrhea, constipation, headache, sore throat, hot flashes, stomach and/or back pain, dizziness, trouble sleeping, and irritation at the injection site (e.g., redness, swelling) may occur. If any of these effects persist or worsen, notify your doctor promptly. Tell your doctor immediately if any of these serious side effects occur: unusual weight loss or loss of appetite, bone pain, hip/pelvis pain, swelling of the arms or legs, trouble breathing. Tell your doctor immediately if any of these unlikely but serious side effects occur: chest pain, unusual tiredness/weakness (fatigue), mental/mood changes, pain during urination, tingling or numbness of the hands/feet. Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: pain and/or redness/warmth in the leg(s), persistent sore throat or fever, persistent vaginal bleeding. If you notice other effects not listed above, contact your doctor or pharmacist.


This medication is not recommended for use if you have the following medical conditions: bleeding problems, low platelet counts (thrombocytopenia), receiving treatment with "blood thinners" (e.g., warfarin). Tell your doctor your medical history, especially of: liver problems, any allergies. Avoid becoming pregnant while using fulvestrant. This medication must not be used during pregnancy because it may cause fetal harm. If you become pregnant or think you may be pregnant, inform your doctor immediately. It is not known whether this drug passes into breast milk. Because of the potential risk to the infant, breast-feeding while using this drug is not recommended.

Drug Interactions

Tell your doctor of all prescription and nonprescription medication you may use. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Do not share this medication with others. Laboratory and/or medical tests may be performed to monitor your progress.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.


Store in the refrigerator between 36 and 46 degrees F (2 and 8 degrees C). Keep all medicines away from children and pets.