Alendronic acid is primarily used in the treatment and prevention of osteoporosis in postmenopausal women and men. It helps to increase bone mass and reduce the risk of fractures, particularly in the spine and hips. Additionally, it is prescribed for managing glucocorticoid-induced osteoporosis and Paget's disease of bone. The medication works by inhibiting bone resorption, thereby maintaining bone density and strength. It is typically administered orally in tablet form, often taken once weekly, and should be taken with water on an empty stomach to ensure optimal absorption. Patients are advised to remain upright for at least 30 minutes after taking the medication to minimize the risk of esophageal irritation. Regular monitoring and adherence to dosing instructions are essential for effective treatment outcomes.