A 55-yr-old post-menopausal woman with osteopenia and no history of breast disease is presented. She was placed on raloxifene HCl 60 mg and soon after developed severe breast pain. The follow-up mammogram, performed prematurely at 6 months, showed a marked increase in breast density. Therapy was accordingly stopped and mastodynia subsided. The patient's mammogram regressed to pre-treatment status after 6 months off-therapy.