Fulvestrant is used to treat hormone receptor positive breast cancer (breast cancer that depends on hormones such as estrogen to grow) in women who have experienced menopause (change of life; end of monthly menstrual periods) and whose breast cancer has worsened after they were treated with antiestrogen medications such as tamoxifen (Nolvadex). Fulvestrant is in a class of medications called estrogen receptor antagonists. It works by blocking the action of estrogen on cancer cells. This can slow or stop the growth of some breast tumors that need estrogen to grow.
Fulvestrant comes as a solution (liquid) to be injected into a muscle in the buttocks. Fulvestrant is administered by a doctor or nurse in a medical office. It is usually given once a month. You may receive your entire dose of medication as a single injection, or the dose may be divided into two injections that are given one after another.
Ask your doctor or pharmacist for a copy of the manufacturer's information for the patient.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Before taking fulvestrant,
- tell your doctor and pharmacist if you are allergic to fulvestrant or any other medications.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention anticoagulants (blood thinners) such as warfarin (Coumadin). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had any bleeding problems or liver disease.
- you should know that fulvestrant should only be taken by women who have undergone menopause and cannot become pregnant. However, if you are pregnant, you should tell your doctor before you begin treatment with this medication. Your doctor may also check to see if you are pregnant before you begin treatment. Tell your doctor if you become pregnant during your treatment with fulvestrant. Fulvestrant may harm the fetus.
- tell your doctor if you are breast-feeding. You should not breast-feed during your treatment with fulvestrant.
Unless your doctor tells you otherwise, continue your normal diet.
If you miss an appointment to receive a dose of fulvestrant, call your doctor as soon as possible.
Fulvestrant may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- stomach pain
- loss of appetite
- sore throat
- pain in bones, joints, or back
- pain, redness, or swelling in the place where your medication was injected
- swelling of the hands, feet, ankles, or lower legs
- difficulty falling asleep or staying asleep
- feelings of numbness, tingling, pricking, or burning on the skin
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- shortness of breath
- chest pain
- difficulty breathing or swallowing
- swelling of the face, throat, tongue, lips, or eyes
Fulvestrant may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Keep all appointments with your doctor.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Last Reviewed: September 1, 2010.