I take calcium supplements and have regular bone scans because estrogen blockers can cause
bone loss, which is usually the cause of the
bone pain. So far, I am holding my own, though. However, I started out with bone density readings off the chart so it might take me a little more time to show any loss. Other side effects are insomnia (if taken before bed....I take mine in the morning, now), minor hair loss, and hot flashes.