Exemestane belongs to the group of cancer-fighting medications known as antineoplastics. Exemestane is often used to treat breast cancers that depend on estrogen for growth and survival. It is used to treat early breast cancer for women who are past menopause and who have previously received 2 to 3 years of tamoxifen, another antineoplastic medication. Exemestane may also be used to treat advanced breast cancer for post-menopausal women who have had the disease continue to grow, even after anti-estrogen treatment.

Exemestane fights cancer by attaching to and inactivating an enzyme called aromatase. This prevents the aromatase enzyme from supplying the estrogen that allows certain types of breast cancers to grow and survive.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended dose of exemestane is 25 mg once daily, at the same time each day, taken after a meal.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a different dose than the ones listed here, do not change the way that you are using the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Exemestane should be stored at room temperature and kept out of the reach of children.

Each white, round, biconvex, film-coated tablet, embossed with the letter "E" on one side, contains 25 mg of exemestane. Nonmedicinal ingredients: crospovidone, hydroxypropyl methylcellulose, magnesium stearate, mannitol, microcrystalline cellulose, polysorbate 80, propylene glycol, silica colloidal anhydrous, sodium starch glycolate, and titanium dioxide.

Do not take exemestane if you:

• are allergic to exemestane or any ingredients of this medication
• have not entered menopause

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal or stomach pain
• burning, tingling, or prickly sensations
• constipation
• diarrhea
• dizziness
• general feeling of tiredness or weakness
• headache
• heartburn
• hot flashes
• increased appetite
• increased sweating
• itching
• joint pain
• loss of hair
• muscle pain or cramps
• nausea
• rash
• trouble sleeping
• weight gain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• bone pain
• flu-like symptoms (e.g., cough, hoarseness, sore throat, fever or chills)
• increased blood pressure (e.g., shortness of breath, fatigue, dizziness, fainting, bluish colour to lips, chest pain or pressure)
• increased cholesterol
• signs of carpal tunnel syndrome (pain or burning in the hands or wrists)
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• signs of a urinary tract infection (e.g., difficult or painful urination, blood in the urine, frequent urge to urinate, lower back or side pain)
• swelling of hands, ankles, feet, or lower legs
• symptoms of liver damage (e.g., yellow skin or eyes, dark urine, clay-coloured stools, loss of appetite, nausea and vomiting, or itching)
• symptoms of a stomach ulcer (e.g., heartburn, burning stomach pain, nausea, vomiting)
• unexplained broken bones
• vaginal bleeding

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a heart attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)
• signs of a blood clot in blood vessels, such as sudden vision change or dizziness, chest pain, pain and swelling in one leg muscle
• sudden development of breathing problems (e.g., shortness of breath, trouble breathing, wheezing, tightness in chest, or fast or irregular breathing)
• signs of a severe allergic reaction (e.g., hives; difficulty breathing; swelling of the face, lips, tongue, or throat)
• signs of bleeding in the stomach or intestines (e.g., dark and tarry stools, blood coming from rectum, vomiting blood or material that looks like coffee grounds, fast heartbeat, weakness or fainting)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.

Cholesterol: Exemestane can cause changes in your cholesterol levels. If you have high blood cholesterol levels, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Driving or operating machinery: Exemestane can cause drowsiness, dizziness, or weakness, affecting your ability to drive or operate machinery. Avoid driving, operating machinery, or performing other potentially hazardous tasks until you have determined how you this medication affects you.

Heart problems: Exemestane may cause an increase in the risk of heart disease. If you have a history of heart disease, heart attack or angina, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you experience symptoms of heart problems such as chest pain, shortness of breath, and swelling of the wrists or legs, contact your doctor immediately.

Kidney function: If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Women taking exemestane may have changes in liver function that produce abnormal liver test results. On rare occasions, liver damage has occurred. If you have reduced liver function or liver disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Osteoporosis: Exemestane may cause a decrease in the density and strength of bones. If you are at risk for developing osteoporosis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pre-menopause: Exemestane does not affect the estrogen that is produced by the ovaries (the main source of estrogen before menopause). The safety and effectiveness of exemestane has not been established for women who have not reached menopause. For these reasons, exemestane is not recommended to treat breast cancer for women who have not reached menopause.

Stomach problems: This medication may increase the risk of stomach problems, including the development of ulcers. If you are taking medications that may cause ulcers, such as nonsteroidal anti-inflammatory medications (NSAIDs), or you have a history of stomach problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pregnancy: Although the effect of exemestane is unclear, there is some evidence suggesting that taking this medication during pregnancy may cause harm to an unborn baby. Exemestane should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if exemestane passes into breast milk. If you are breast-feeding and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

There may be an interaction between exemestane and any of the following:

• bosentan
• carbamazepine
• dabrafenib
• efavirenz
• estrogens (e.g., conjugated estrogen, estradiol, ethinyl estradiol)
• etravirine
• fosphenytoin
• lumacaftor and ivacaftor
• methadone
• mitotane
• modafinil
• phenobarbital
• phenytoin
• primidone
• rifampin
• St. John's wort
• warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.