Today I had a bone density test, and afterward I talked to a NP, who prescribed Fosamax, because she said I have osteopenia. My T-score was -1.3. She said I should take Fosamax because I am on Arimidex after breast cancer, I have broken some bones from 2 falls and my mother had a hip fracture in her 80's. I am still very active: I hike, take 4 exercise classes a week, including weight lifting, and I take Vitamin D and Calcium. I'm concerned about side-effects from Fosamax. My brother-in-law developed bone Necrosis of the jaw. Do I really need to take this drug????