Nitrogenous bisphosphonate act on bone metabolism by binding and blocking the enzyme farnesyl diphosphate synthase (FPPS) in the HMG-CoA reductase pathway (also known as the mevalonate pathway).
In pharmacology, bisphosphonate (also called: diphosphonates) is a class of drugs that inhibits the resorption of bone. Its uses include the prevention and treatment of osteoporosis, osteitis deformans ("Paget's disease of bone"), bone metastasis (with or without hypercalcemia), multiple myeloma and other conditions that feature bone fragility
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Bisphosphonate: A class of drugs used to strengthen bone. Bone is in a constant state of remodeling, whereby new bone is laid down by cells called osteoblasts while old bone is removed by cells called osteoclasts. Bisphosphonates inhibit bone removal (resorption) by the osteoclasts. Bisphosphonates are used to treat osteoporosis and the bone pain from diseases such as metastatic breast cancer, multiple myeloma, and Paget's disease. The bisphosphonates include Fosamax (alendronate) and Aredia (pamidronate).