Several different kinds of cancer including bone cancer, breast cancer that has spread to bones, and multiple myeloma weaken bones and make them so weak that they will collapse or fracture. Pamidronate strengthens bones - it doesn't have any effect on the cancer but it makes bones more stable and prevents them from breaking. In research studies, pamidronate has also been shown to reduce bone pain in both multiple myeloma and metastatic breast cancer.
Osteoclasts are bone cells, which break down bone tissue.
In normally functioning bones, these cells are followed by cells that lay down new tissue. However, in multiple myeloma and metastatic breast cancer this relationship is unbalanced and the bone tissue is broken down too quickly. Biphosphonates, such as pamidronate, prevent the maturation and formation of the osteoclasts, thus preventing bone resorption. Over a 2-4 hour period. Studies conducted have shown that pamidronate has few side effects.