Role of alendronate and risedronate in preventing and treating osteoporosis.

Alendronate and risedronate, the two oral bisphosphonates approved in the United States for preventing and treating osteoporosis, have never been compared in direct head-to-head trials, but they appear to have similar pharmacokinetics, drug interactions, adverse effect profiles, and efficacy. Alendronate, however, can be given as a once-weekly dose, whereas risedronate is not yet available in this dosage form. On the other hand, alendronate is not approved for preventing glucocorticoid-induced osteoporosis, whereas risedronate carries this indication.