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URL of this page: https://medlineplus.gov/druginfo/meds/a607006.html

Exemestane

pronounced as (ex e mes' tane)

Why is this medication prescribed?

Exemestane is used to treat early breast cancer in women who have experienced menopause ('change of life'; end of monthly menstrual periods) and who have already been treated with a medication called tamoxifen (Nolvadex) for 2 to 3 years. This medication is also used to treat breast cancer in women who have experienced menopause whose breast cancer has worsened while they were taking tamoxifen. Exemestane is in a class of medications called aromatase inhibitors. It works by decreasing the amount of estrogen produced by the body. This can slow or stop the growth of some breast tumors that need estrogen to grow.

How should this medicine be used?

Exemestane comes as a tablet to take by mouth. It is usually taken once a day after a meal. Take exemestane at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take exemestane exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

You may need to take exemestane for several years or longer. Continue to take exemestane even if you feel well. Do not stop taking exemestane without talking to your doctor.

Other uses for this medicine

Exemestane is also sometimes used to treat a certain type of breast cancer in women who not yet experienced menopause. Talk to your doctor about the risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking exemestane,

  • tell your doctor and pharmacist if you are allergic to exemestane or any other medications.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: carbamazepine (Carbatrol, Epitol, Tegretol); medications that contain estrogen such as hormone replacement therapy and hormonal contraceptives (birth control pills, patches, rings, and injections); phenobarbital; phenytoin (Dilantin); and rifampin (Rifadin, in Rifater, in Rifamate). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor what herbal products you are taking, especially St John's wort.
  • tell your doctor if you have or have ever had osteoporosis (condition in which the bones are fragile and break easily), liver or kidney disease.
  • tell your doctor if you are pregnant or plan to become pregnant. You will need to have a negative pregnancy test within 7 days before you begin to take exemestane. You should use birth control to avoid pregnancy during your treatment with exemestane and for 1 month after your final dose. If you become pregnant while taking exemestane, call your doctor immediately. Exemestane may harm the fetus.
  • tell your doctor if you are breastfeeding. You should not breastfeed during your treatment with exemestane and for 1 month after your final dose.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next 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 side effects can this medication cause?

Exemestane may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • hot flushes
  • sweating
  • muscle or joint pain
  • tiredness
  • headache
  • dizziness
  • feeling worried or anxious
  • depression
  • difficulty falling asleep or staying asleep
  • nausea
  • vomiting
  • increased appetite
  • diarrhea
  • hair loss
  • red, itchy skin
  • changes in vision
  • swelling of the arms, hands, feet, ankles, or lower legs

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

  • shortness of breath
  • chest pain

Your bone mineral density (BMD; a measure of the strength of the bones) may decrease while you are taking exemestane. This may increase the chance that you will develop osteoporosis (condition in which the bones are fragile and break easily). Talk to your doctor about the risks of taking exemestane.

Exemestane may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

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).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/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 other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to exemestane.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

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.

Brand names

  • Aromasin®
Last Revised - 02/15/2022