Teriparatid

Teriparatide is a recombinant form of human parathyroid hormone consisting of the amino-terminal 34 amino acids (PTH 1-34). It is an osteoanabolic agent indicated for the treatment of osteoporosis in adults at high risk of fracture, including postmenopausal women and men, and for glucocorticoid-induced osteoporosis. Its mechanism involves preferential stimulation of osteoblast activity over osteoclast activity, leading to increased bone formation and improved bone mass and microarchitecture.

The medication is administered by subcutaneous injection once daily, with a typical dose of 20 micrograms. Injections are given in the abdomen or thigh and the injection site should be rotated. Treatment is generally limited to a total of up to 2 years of lifetime use due to concerns from animal studies about osteosarcoma risk, with the exact duration guided by clinical circumstances and local guidelines.

Contraindications include hypercalcemia, suspicion or known osteosarcoma or other bone malignancies, metabolic bone diseases other than osteoporosis, and hypersensitivity to teriparatide or its excipients. Caution is advised in patients with significant renal impairment or prior skeletal irradiation, and all patients should receive adequate calcium and vitamin D supplementation to support bone health.

Common adverse effects include nausea, leg cramps, dizziness, injection-site reactions, and headaches. There is a potential risk of hypercalcemia; rare concerns regarding osteosarcoma have influenced labeling and duration recommendations. Regulatory status and availability vary by country, but teriparatide is typically prescription-only and marketed under various brand names.