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Fulvestrant - Injection

Pronunciation: ful-VES-trant

Common Brand Name(s): Faslodex

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Uses

Fulvestrant is used to treat certain types of breast cancer. Breast cancer cells need the hormone estrogen in order to grow. Fulvestrant works by blocking the effect of estrogen, slowing tumor cell growth.

How To Use

Read the Patient Information Leaflet if available from your pharmacist before you start using fulvestrant and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

This medication is given by slow injection into the buttock muscle by a health care professional. It is given as directed by your doctor, usually every 2 weeks for the first 3 doses and then monthly. The dosage is based on your medical condition.

Side Effects

Pain/swelling/redness at the injection site, nausea/vomiting, loss of appetite, constipation, diarrhea, upset stomach, dizziness, tiredness, headache, hot flashes, or trouble sleeping may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

  • numbness/tingling of arms/legs
  • back/leg pain
  • bone/joint pain
  • mental/mood changes (such as anxiety, depression)
  • shortness of breath
  • cough that doesn't go away
  • burning/painful/frequent urination
  • unusual tiredness
  • signs of infection (such as sore throat that doesn't go away, fever, chills)

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before using this medication, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients (such as benzyl alcohol), which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

  • liver disease
  • bleeding problems
  • low platelet counts (thrombocytopenia)

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using fulvestrant. Fulvestrant may harm an unborn baby. A pregnancy test should be done within 7 days of starting this medication. Ask your doctor about reliable forms of birth control while using this medication and for 1 year after stopping treatment. Do not use birth control that contains estrogen. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.

It is unknown if this drug passes into breast milk. Because of the possible risk to the infant, breast-feeding while using this drug and for 1 year after stopping treatment is not recommended. Consult your doctor before breast-feeding.

Drug Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

This medication may interfere with certain lab tests (such as estradiol levels), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center.

Notes

Lab and/or medical tests (such as liver function) should be done while you are using this medication. Keep all medical and lab appointments. Consult your doctor for more details.

Missed Dose

It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule.

If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.

Storage

Not applicable. This medication is given in a clinic or doctor's office and will not be stored at home.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.