Patients with advanced breast cancer may take tamoxifen for varying lengths of time, depending on their response to this treatment and other factors. When used as adjuvant therapy for early stage breast cancer, tamoxifen is generally prescribed for 5 years. However, the ideal length of treatment with tamoxifen is not known.
How Often Should I Take Tamoxifen?
Two studies have confirmed the benefit of taking adjuvant tamoxifen daily for 5 years. These studies compared 5 years of treatment with tamoxifen with 10 years of treatment. When taken for 5 years, the drug reduces the risk of recurrence of the original breast cancer and also reduces the risk of developing a second primary cancer in the other breast. Taking tamoxifen for longer than 5 years is not more effective than 5 years of therapy.
What is Tamoxifen
Tamoxifen is an oral selective estrogen receptor modulator which is used in breast cancer treatment, and is currently the world's largest selling breast cancer treatment. It is used for the treatment of early and advanced breast cancer in pre- and post-menopausal women. It is also approved by the FDA for the reduction of the incidence of breast cancer in women at high risk of developing the disease. It has been further approved for the reduction of contralateral (in the opposite breast) breast cancer.
Tamoxifen and Cancer
Tamoxifen is used to reduce the risk of breast cancer for women who:
1. are at high risk of breast cancer but have no personal history of the disease
2. have non-invasive, hormone-receptor-positive breast cancer, or DCIS (ductal carcinoma in situ)
3. have hormone-receptor-positive invasive breast cancer at any stage.
Tamoxifen is sometimes used to treat gynecomastia in men. Tamoxifen is also used by bodybuilders in a steroid cycle to try and prevent or reduce drug-induced gynecomastia caused by steroids that are used in the same cycle.
Tamoxifen is also used to treat infertility in women with anovulatory disorders. A dose of 10-40 mg per day is administered in days 3-7 of a woman's cycle.
