Teriparatide is a parathyroid hormone or PTH analog that is usually administered in a pulsatile fashion. When administered in short bursts, teriparatide actually increases osteoblast activity, which causes new bone formation. This new bone formation is very useful for treating patients with osteoporosis. Hypercalcemia is the key side effect to remember for teriparatide.

Key Points

  • Teriparatide
    • Mechanism
      • Recombinant PTH analog given subcutaneously daily
        • Increases osteoblast activity/lays down bone when administered in pulsatile fashion (during a “window period”)
    • Clinical Use
      • Osteoporosis
        • Causes increased bone growth compared to antiresorptive therapies (e.g., bisphosphonates)
    • Adverse effects
      • Hypercalcemia
        • PTH-like activity leads to increased gastrointestinal calcium absorption and renal tubular calcium reabsorption
      • Increased risk of Osteosarcoma
        • Only seen in rodents; not proven in people
        • Avoid in people with increased risk (e.g. Paget’s disease of bone, prior radiation, etc.)