Tamoxifen Citrate, a Selective Estrogen Receptor Modulator (SERM), competes with estrogen for binding sites in the Estrogen Receptor (ER) in target tissues such as breast. The drug has been in use for over 30 years with a proven high therapeutic index and significant efficacy. The drug is effective in reducing breast cancer recurrence and improving patient's survival across all age groups. The drug is effective in young pre-menopausal breast cancer patients [13-15] . Recently, it has been reported (16) that breast cancer survivors who take tamoxifen for ten years have half the risk of dying from estrogen receptor positive breast cancer. Therefore the new ASCO (American Society of Clinical Oncology ) recommendations are to increase the period of tamoxifen treatment.