A friend of mine had a Reclast infusion which sent her straight to the hospital. She said that the pain in her body was horrendous and felt like all of her bones were broken, especially in her back. She was never so frightened in her life. The symptoms improved and she was soon fine, but she said she would never take Reclast again. She was later told that if they give you an IV of fluids along with the Reclast, or you drink a lot of water, that the symptoms are less likely to happen. Something like that anyway.
I have significant osteoporosis, and Reclast is definitely off my list of possible medications.