ACTONEL COMBI

Risedronic acid is a pyridinyl bisphosphonate that binds to bone hydroxyapatite and inhibits osteoclast-mediated bone resorption. The bone turnover is reduced while the osteoblast activity and bone mineralisation is preserved.

Calcium carbonate releases, in a pH-dependent manner, calcium ions in the stomach. Calcium carbonate is widely used as antacid and extensively used as a dietary supplement.

In its biologically active form vitamin D₃ stimulates intestinal calcium absorption, incorporation of calcium into the osteoid, and release of calcium from bone tissue. In the small intestine it promotes rapid and delayed calcium uptake. The passive and active transport of phosphate is also stimulated.