Tamoxifen has been used in the treatment of advanced breast cancer since 1978. Additionally, it has been used in the adjuvant setting after lumpectomy or mastectomy to prevent recurrence of breast cancer. Raloxifene, introduced on the market just last year, is prescribed to prevent osteoporosis in postmenopausal women. It is not indicated for the treatment of breast cancer, however researchers have discovered it may also reduce the risk of breast cancer. Never before have drugs been approved as being effective in reducing the risk of developing cancer.
Tamoxifen also increases menopausal symptoms such as hot flashes and vaginal discharge.
Tamoxifen also has some positive side effects. Tamoxifen has been shown to moderately reduce bone fractures and slightly increase bone mineral density, although it appears to be inferior to other drugs used to treat osteoporosis. Tamoxifen has also been shown to reduce cholesterol levels, however there is little evidence of beneficial effects on heart disease. Recently, the results of a new study suggested that raloxifene, an osteoporosis drug, may be effective in breast cancer risk reduction. This result is promising but is based on a limited number of breast cancers.