Bisphosphonates are an important class of drugs originally commercialised in the mid to late 20th century. They are used for the treatment of osteoporosis and other bone disorders that cause bone fragility and diseases where bone resorption is excessive. Osteoporosis is common in post-menopausal women and patients in corticosteroid treatment where biphosphonates have been proven a valuable treatment and also used successfully against Paget's disease, myeloma, bone metastases and hypercalcemia. Bisphosphonates reduce breakdown of bones by inhibiting osteoclasts, they have a long history of use and today there are a few different types of bisphosphonate drugs on the market around the world.