Bone drugs (osteoporosis)
also: bisphosphonate · alendronate · denosumab · calcium vitamin D · teriparatide
Overview
Osteoporosis and bone-protection therapy. Bisphosphonates are first-line; the dosing instructions and jaw osteonecrosis are the tested points.
Mechanism
Bisphosphonates bind hydroxyapatite and inhibit osteoclast-mediated bone resorption (osteoclast apoptosis) → increased bone density. Denosumab is a RANK-ligand monoclonal antibody → inhibits osteoclast formation. Calcium/vitamin D correct substrate deficiency. Teriparatide (PTH analogue) is anabolic (stimulates bone formation).
Indications
- Osteoporosis (fragility fracture prevention)
- Steroid-induced osteoporosis prophylaxis
- Hypercalcaemia of malignancy, Paget disease (bisphosphonates)
The agents
weekly
Take upright, empty stomach, with water, stay upright 30 min (oesophagitis).
annual
Use if oral not tolerated; acute-phase flu-like reaction.
SC 6-monthly
Rebound vertebral fractures if stopped — don't delay doses.
Co-prescribed to ensure replete before antiresorptives.
Adverse effects
Hence the upright/water/empty-stomach rule.
Dental check before; risk ↑ with IV, dental extraction.
Long-term; review need after ~5 years.
Cautions & contraindications
Interactions
- Calcium/iron/antacids block oral bisphosphonate absorption (separate)
Monitoring & kinetics
Calcium + vitamin D (replete before starting),Dental review; renal function; review bisphosphonate after ~5 years
Oral (strict dosing instructions) or IV/SC. Antiresorptive vs anabolic (teriparatide) distinction.
Source: NICE NG — Osteoporosis (CKS) · BNF — Bisphosphonates