Anastrozole is a first-line treatment of breast cancer in postmenopausal women. It slows the growth of advanced cancer within the breast and cancer that has spread to other parts of the body. Anastrozole is also used to treat advanced breast cancer in postmenopausal women whose disease has spread to other parts of the body following treatment with tamoxifen (Nolvadex), another anticancer drug. Anastrozole can also be prescribed along with other drugs to treat the early stages of breast cancer in postmenopausal women.
Anastrozole combats the kind of breast cancer that thrives on estrogen. One of the hormones produced by the adrenal gland is converted to a form of estrogen by an enzyme called aromatase. Anastrozole suppresses this enzyme and thereby reduces the level of estrogen circulating in the body.
Anastrozole, like many other anticancer medications, may prolong survival and improve quality of life. To keep Anastrozole working properly, it's important to continue taking it even when you don't feel well. If you develop bothersome side effects, call your doctor. He or she can recommend ways to reduce your discomfort.
Anastrozole tablets contain the active ingredient anastrozole, which is a type of drug known as a non-steroidal aromatase inhibitor. It works by preventing the action of an enzyme in the body called the aromatase enzyme.
The aromatase enzyme is involved in the production of the female sex hormone, oestrogen. In women who have passed the menopause, oestrogen is mainly produced by this enzyme. In postmenopausal women the aromatase enzyme converts the sex hormones androstenedione (produced by the ovary), and testosterone, into oestrogen. Anastrozole prevents this conversion by blocking the action of the aromatase enzyme. This causes oestrogen levels in the body to fall.
Many breast cancers are sensitive to oestrogen, and they need this hormone to grow. These types of breast cancer are termed 'hormone receptor positive'. Oestrogen binds to oestrogen receptors on the breast cancer cells and causes changes within the cells that result in faster growth of the cancer.
By lowering the levels of oestrogen in the body, anastrozole effectively starves the breast cancer cells, thus helping to stop them grow.
Anastrazole helps prevent breast cancer from spreading to other areas of the body and also reduces risk of developing cancer in the other breast.
Anastrazole is only effective in postmenopausal women, since before the menopause oestrogen is mainly produced by the ovaries and not by the aromatase enzyme.
Why is this drug prescribed?
- treating postmenopausal women who have had surgery to remove early hormone receptor positive breast cancer. it can either be used for five years immediately following the surgery or after two to three years of taking tamoxifen.;
- advanced breast cancer in women who have passed the menopause;
- weight gain;
- weakness;
- vomiting;
- vaginal discharge or inflammation;
- urinary tract infection;
- swelling of arms and legs;
- sweating;
- stomach and intestinal upset;
- sore throat;
- rash shortness of breath;
- pins and needles;
- pelvic pain and stiffness;
- pain;
- osteoporosis;
- nausea;
- loss of appetite;
- joint disease or pain;
- insomnia;
- infection;
- hot flashes;
- high blood pressure or cholesterol;
- heart disease;
- headache;
- fractures;
- flu-like symptoms;
- dry mouth;
- dizziness;
- diarrhea;
- depression;
- cough;
- constipation;
- chest pain;
- cataracts;
- breast pain;
- bone pain;
- back pain;
- arthritis;
- anxiety;
- accidental injury;
- weakness or loss of strength (asthenia);
- very rare severe skin reactions (eg stevens-johnson syndrome);
- vaginal dryness;
- vaginal bleeding;
- sleepiness (somnolence);
- rash;
- raised cholesterol levels;
- nausea and vomiting;
- mood disturbances;
- loss of appetite;
- joint pain or stiffness;
- hot flushes;
- headache;
- hair thinning;
- diarrhoea;
- decreased bone density;
- abdominal pain;
ADULTS
The usual dose is a 1-mg tablet taken once a day. If Anastrozole is being used as an initial treatment for advanced breast cancer, you will continue taking the medication until it no longer works against the tumor. The optimal duration of therapy for early breast cancer has not been determined.
