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Bisphosphonates bind to hydroxyapatite on bone surfaces and are taken up by osteoclasts during resorption. Nitrogen-containing agents inhibit farnesyl pyrophosphate synthase, while non-nitrogen agents form toxic ATP analogs; both pathways impair osteoclast activity and promote apoptosis. The resulting reduction in bone turnover can increase bone mineral density and lower fracture risk. Their uses include osteoporosis, Paget disease, hypercalcemia of malignancy, and bone metastases. Oral administration requires attention to fasting, water intake, separation from divalent cations, and remaining upright. Important safety considerations include gastrointestinal irritation, hypocalcemia, renal impairment, and uncommon serious complications. The broader lesson also compares related therapies such as denosumab, romosozumab, calcitonin, and gallium nitrate.