Arimidex (anastrozole) lowers estrogen levels in postmenopausal women, which may slow the growth of certain types of breast tumors that need estrogen to grow in the body.
Arimidex is used to treat breast cancer in postmenopausal women. It is often given to women whose cancer has progressed even after taking tamoxifen (Nolvadex, Soltamox).
You should not use Arimidex if you are allergic to anastrozole, if you are breast-feeding a baby, or if you have not yet completed menopause. Arimidex is not for use in men or children.
To make sure you can safely take Arimidex, tell your doctor if you have any of these other conditions:
- heart disease;
- circulation problems;
- a history of stroke or blood clot;
- severe liver disease;
- high cholesterol; or
- osteoporosis or low bone mineral density.
Get emergency medical help if you have any of these signs of an allergic reaction to Arimidex: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have a serious side effect such as:
- sudden numbness or weakness, especially on one side of the body;
- sudden severe headache, confusion, problems with vision, speech, or balance;
- a bone fracture;
- swollen glands;
- feeling short of breath;
- nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
- swelling in your hands or feet; or
- severe skin reaction — fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Less serious Arimidex side effects may include:
- numbness, tingling, cold feeling, or weakness in your hand or wrist;
- problems with your fingers while gripping;
- hot flashes;
- joint pain or stiffness;
- depression, mood changes, sleep problems (insomnia);
- cough, sore throat;
- thinning hair;
- mild nausea, vomiting; or
- back pain, bone pain.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.