Bone Protection Drugs

Expansion

Antiresorptive

• Bisphosphonates (alendronate, zoledronate): taken up by osteoclasts and induce apoptosis. Poor oral absorption, hence the strict administration rules. Adverse effects: oesophagitis, atypical femoral fracture, osteonecrosis of the jaw (rare; dental assessment first), acute phase reaction with intravenous dosing
• Denosumab: monoclonal antibody against RANK ligand, given 6 monthly. Effect is not retained after stopping, with rapid rebound bone loss and vertebral fracture, so it must be followed by a bisphosphonate rather than simply discontinued
• Hormone replacement therapy and raloxifene

Anabolic

• Teriparatide: intermittent parathyroid hormone, which paradoxically favours formation. Daily injection, limited duration
• Romosozumab: anti-sclerostin, both anabolic and antiresorptive; cardiovascular caution

Foundation measures apply to all: adequate calcium and vitamin D, weight-bearing exercise, smoking and alcohol reduction, and falls assessment.

Treatment is guided by fracture risk (FRAX or QFracture) rather than bone density alone, and steroid-induced osteoporosis warrants early protection since bone loss is fastest in the first months.