How anastrozole works
Anastrozole is a so-called reversible aromatase inhibitor. The active ingredient blocks the enzyme aromatase and thus prevents the formation of female sex hormones (estrogen synthesis).
During the development of the female sex organs in puberty, the body selectively secretes estrogens to stimulate the tissues concerned to grow. After the end of puberty, this process is complete. The estrogen that continues to be produced only controls the female cycle, which makes pregnancies possible.
Sometimes, however, an error occurs in this complex control process. Then it can happen that breast tissue, for example, still reacts to female hormones and grows in dependence on them. This uncontrolled, hormone-dependent growth can then lead to a malignant growth (tumor) – breast cancer.
Anastrozole is only used in post-menopausal women, in whom estrogen production is already massively reduced.
Absorption, breakdown and excretion
After ingestion, the active substance reaches its highest levels in the body within two hours. It is largely broken down by the liver and excreted in the urine. Only a small amount leaves the body unchanged.
Anastrozole remains in the body for a relatively long time. About two days after taking it, only about half has been excreted.
When is anastrozole used?
Anastrozole is used to treat hormone-sensitive advanced breast cancer in post-menopausal women.
Therapy with anastrozole is given over a long period of time, sometimes several years. It may be designed as adjuvant (supportive) drug treatment or, if a cure is no longer possible, as palliative (improving quality of life) therapy.
How anastrozole is used
What are the side effects of anastrozole?
Anastrozole may cause headache, flushing, nausea, rash, joint pain, joint inflammation, bone loss, and weakness as very common side effects. “Very common” means that these adverse effects occur in more than one in ten patients.
Common side effects (occurring in one to ten percent of patients) include high cholesterol, loss of appetite, drowsiness, taste disturbances, discomfort, diarrhea, vomiting, elevated liver enzyme levels, hair loss, allergic reactions, vaginal dryness, vaginal bleeding, muscle and bone pain.
What should be considered when taking anastrozole?
Contraindications
Anastrozole must not be used in:
- hypersensitivity to the active substance
- pregnant or breastfeeding women
Patients with severe liver or kidney dysfunction should be treated with anastrozole only in exceptional cases.
Drug interactions
The concomitant intake or use of tamoxifen or estrogens attenuates the effect of anastrozole.
In patients with osteoporosis or an increased risk of osteoporosis, bone density should be measured before starting and regularly during treatment with anastrozole. If necessary, timely action can be taken to prevent a reduction in bone density.
Age Limitation
Men, children, adolescents, and pre-menopausal women should not be treated with anastrozole. However, this may change in the future. Studies are currently underway to determine whether elevated estrogen levels in boys and men can be treated with anastrozole.
Pregnancy and breastfeeding
Anastrozole is contraindicated during pregnancy and breastfeeding.
How to get medicine with anastrozole
The breast cancer drug anastrozole is available only on prescription in Germany, Austria, and Switzerland. It can therefore only be obtained from pharmacies on prescription.
