Pronounce: ex-e-MES-tane
Classification: Aromatase Inhibitor
Aromatase is an enzyme that helps produce the hormone estrogen. Some cancers use estrogen to grow. By inhibiting or blocking aromatase, these estrogen-driven cancer cells may stop growing.
Exemestane is an aromatase inactivator, which works to decrease the overall levels of estrogen in a woman's body. In women who have gone through menopause, estrogen is mainly produced by the aromatase enzyme, which converts androgens (sex hormones produced by the adrenal glands) into estrogens. Exemestane binds to aromatase, changing the protein permanently. This change "turns off" aromatase so that it can no longer make estrogen. While estrogen may not actually cause breast cancer, it is necessary for the cancer to grow in certain breast cancers. With estrogen blocked, the cancer cells that feed off estrogen may not be able to survive.
Exemestane comes as a tablet to take by mouth. The tablet should be taken once a day after a meal. Take exemestane at around the same time every day.
Do not take your medication with a high-fat meal, as this can increase the medication levels in your blood. The blood levels of this medication can also be affected by certain medications. These include: medications with estrogen including birth control pills or patches and hormone replacement therapy, rifampin, carbamazepine, phenobarbital, phenytoin, and St. John’s wort. Be sure to tell your healthcare provider about all medications and supplements you take. Your blood level of Vitamin D will be checked prior to starting this medication. If your Vitamin D level is low, you may require a supplement.
It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed.
Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your healthcare provider or pharmacist). This medication should not be stored in a pillbox. Keep containers out of reach of children and pets.
If a caregiver prepares your dose for you, they should consider wearing gloves or pour the pills directly from their container into the cap, a small cup, or directly into your hand. They should avoid touching the pills. They should always wash their hands before and after giving you the medication. Pregnant or nursing women should not prepare the dose for you. Ask your oncology team where to return any unused medication for disposal. Do not flush down the toilet or throw in the trash.
Exemestane is available through both specialty pharmacies and retail/mail order pharmacy; depending on your prescription drug insurance plan. Your oncology team will work with your prescription drug plan to identify an in-network specialty/retail/mail order pharmacy for medication distribution.
This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals depending upon prescription drug coverage. Co-pay cards, which reduce the patient co-pay responsibility for eligible commercially (non-government sponsored) insured patients, may also be available. Your care team can help you find these resources if they are available.
There are a number of things you can do to manage the side effects of exemestane. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:
There are a few things you can do to help with hot flashes. Several medications have been shown to help with symptoms, including clonidine (a blood pressure medication), low doses of certain antidepressants (such as venlafaxine and fluoxetine), and gabapentin. Talk to your healthcare team about these prescription products to determine if they are right for you.
Non-medical recommendations include:
Aromatase inhibitor medications can cause joint or muscle aches and pains, which can interfere with quality of life. Be sure to talk to your oncology care team if you develop this side effect. This pain is caused mainly by swelling in the joints, which is best treated by a non-steroidal anti-inflammatory (NSAID), such as ibuprofen (Advil/Motrin), naproxen (Aleve), and celecoxib (Celebrex). Be sure to discuss which pain relievers you can safely take with your oncology team, as these are not without their own side effects. Studies have shown that acupuncture and gentle stretching and exercise may also help reduce this pain.
Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team for helpful tips on dealing with this side effect.
Talk to your oncology care team so they can prescribe medications to help you manage nausea and vomiting. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy/fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try saltines, or ginger ale to lessen symptoms.
Call your oncology care team if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.
This medication should only be given to women who have gone through menopause. Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant while on this medication. If you do become pregnant you should contact your care team immediately. Effective birth control is necessary during treatment and for at least 1 month after treatment. You should not breastfeed while receiving this medication or for 1 month after your last dose.
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