Why is this medicine prescribed?
Imlunestrant is used to treat certain types of breast cancer. Imlunestrant is in a class of medications called estrogen receptor antagonists. It works by helping to stop tumor growth.
Are there other uses for this medicine?
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
How should this medicine be used?
Imlunestrant comes as a tablet to take by mouth. Take once a day on an empty stomach at least 2 hour before or 1 hours after food. Take imlunestrant at around the same time every day. Your doctor will decide how long you should take imlunestrant based on how your body responds to treatment.
Take imlunestrant exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Swallow the tablets whole; do not split, chew, or crush them.
Your doctor may need to adjust your dose based on certain side effects you may experience. It is important to regularly discuss how you are feeling for healthcare providers.
What special precautions should I follow?
Before taking imlunestrant,
- tell your doctor or pharmacist if you are allergic to this medication, any part of this medication, or any other medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
- some medications should not be taken with imlunestrant. Other medications may cause dosing changes or extra monitoring when taken with imlunestrant. Make sure you have discussed any medications you are currently taking or plan to take before starting imlunestrant with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking imlunestrant, please get the advice of your doctor or pharmacist.
- the following nonprescription or herbal products may interact with imlunestrant: St. John's Wort. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking imlunestrant. Do not start any of these medications while taking imlunestrant without discussing with your healthcare provider.
- tell your doctor if you have or have ever had liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or if you plan to father a child. You or your partner should not become pregnant while you are taking imlunestrant. You may be required to have a pregnancy test before you start treatment. You or your partner should use birth control to prevent pregnancy during your treatment and for 1 week after your final dose. Talk to your doctor about birth control methods that you or your partner can use during your treatment. If you or your partner becomes pregnant while taking imlunestrant, call your doctor immediately.
- do not have any vaccinations without talking to your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking imlunestrant.
What special dietary instructions should I follow?
Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medication.
What should I do if I forget to take a dose?
Take the missed dose as soon as you remember it. However, if more than 6 hours have passed since the scheduled dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What should I do in case of overdose?
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
What side effects can this medicine cause?
Imlunestrant may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- muscle and joint pain
- extreme tiredness
- diarrhea, constipation, nausea, abdominal pain
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- feeling tired or weak, pale skin, dizziness or lightheadedness, feeling of rapid or irregular heartbeat, headaches, cold hands or feet, craving nonfood items
- fever, chills, cough, body aches
- lower abdominal pain, yellowing of skin or whites of eyes, nausea, loss of appetite, dark urine, clay-colored stools
- easy bruising, prolonged bleeding from cuts, bleeding gums, heavy periods, small red or purple spots on skin
- muscle cramps or spasms, numbness or tingling in hands, feet or around the mouth, confusion, seizures
Imlunestrant may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( https://www.fda.gov/Safety/MedWatch ) or by phone ( 1-800-332-1088).What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to imlunestrant.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.