What they are: Bisphosphonates are medications that limit the activity of certain bone cells, called osteoclasts, which help cause the bone weakening and destruction that can happen when breast cancer spreads to the bone.
Examples include: Zometa and Reclast (chemical name: zoledronic acid); Aredia (chemical name: pamidronate); Fosamax (alendronate sodium); Actonel (chemical name: risedronate). Another option is Xgeva (chemical name: denosumab), which technically is not a bisphosphonate but also works to limit the activity of osteoclasts.
What they're used for: Bisphosphonates are used to reduce bone complications and bone pain caused by advanced-stage breast cancer that has spread to the bone.
How they're taken: Bisphosphonates are often given intravenously along with chemotherapy, but sometimes taken by mouth.
Possible side effects include: