Bisphosphonates (also called diphosphonates) are a class of drugs that prevent the loss of bone mass, used to treat osteoporosis and similar diseases. They are called bisphosphonates because they have two phosphonate (PO3) groups, and are similar in structure to pyrophosphate. Evidence shows that they reduce the risk of osteoporotic fracture in those who have had previous fractures however do not reduce fracture risk in those with osteoporosis who have not previously had a fracture. Bone undergoes constant turnover and is kept in balance by osteoblasts creating bone and osteoclasts destroying bone...