Aromasin tablets contain the active ingredient exemestane, which is a type of medicine called an aromatase inhibitor. It works by preventing the action of an enzyme in the body called the aromatase enzyme.
The aromatase enzyme is involved in producing the female sex hormone, oestrogen, in women who have gone through the menopause. The enzyme converts the sex hormones androstenedione (produced by the ovaries), and testosterone, into oestrogen. Exemestane prevents this conversion by blocking the action of the aromatase enzyme. This causes a reduction in oestrogen levels.
Most breast cancers are sensitive to oestrogen, and their growth is stimulated by this hormone. By lowering the levels of oestrogen in the body, exemestane starves the breast cancer cells and stops them from growing. Exemestane is only effective in treating breast cancers that are sensitive to oestrogen (these are sometimes called oestrogen receptor positive cancers).
Exemestane is only effective in postmenopausal women, since before the menopause, oestrogen is mainly produced directly by the ovaries and not by the action of the aromatase enzyme.
Exemestane is used to treat breast cancer in women who are postmenopausal, either naturally, or as a result of medical treatment. It is used for treating women with early invasive cancers, after they have completed two to three years of treatment with tamoxifen. It is also used to treat advanced cancers, where the cancer has continued to grow despite using other anti-oestrogen medicines.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
The side effects listed above may not include all of the side effects reported by the drug's manufacturer.For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
You should tell your doctor or pharmacist what medicines you are taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Likewise, you should always check with your doctor or pharmacist before taking any new medicines during treatment with this one, so they can check that the combination is safe.
Medicines that contain oestrogens, for example hormone replacement therapy (HRT), should not be taken in combination with this medicine, as they will oppose its action and make it less effective at treating the cancer.
The following medicines may potentially reduce the blood level of this medicine and could make it less effective:
There are currently no other medicines available in the UK that contain exemestane as the active ingredient.