indication

For the treatment of osteoporosis in men and postmenopausal women who are at high risk for having a fracture. Also used to increase bone mass in men with primary or hypogonadal osteoporosis who are at high risk for fracture.

pharmacology

Clinical trials indicate that teriparatide increases predominantly trabecular bone in the lumbar spine and femoral neck; it has less significant effects at cortical sites. The combination of teriparatide with antiresorptive agents is not more effective than teriparatide monotherapy. The most common adverse effects associated with teriparatide include injection-site pain, nausea, headaches, leg cramps, and dizziness. After a maximum of two years of teriparatide therapy, the drug should be discontinued and antiresorptive therapy begun to maintain bone mineral density.

mechanism of action

Teriparatide is the portion of human parathyroid hormone (PTH),amino acid sequence 1 through 34 of the complete molecule which contains amino acid sequence 1 to 84. Endogenous PTH is the primary regulator of calcium and phosphate metabolism in bone and kidney. Daily injections of teriparatide stimulate new bone formation leading to increased bone mineral density.

toxicity

Effects of overexposure may include headaches, dizziness, dizziness, decreased blood pressured, decreased fetal survival, leg cramps, changes in clinical chemistry including increased in blood levels of calcium, decreased serum phosphorous, and increased urinary calcium and phosphorus.

biotransformation

Hepatic

absorption

Bioavailability is 95% following subcutaneous injection.

route of elimination

Peripheral metabolism of PTH is believed to occur by non-specific enzymatic mechanisms in the liver followed by excretion via the kidneys. The 24-hour urine excretion of calcium was reduced by a clinically unimportant amount (15%).