Name: Synthetic parathyroid hormone (Teriparatide, Parathar)
Class: Hormone
Mechanism: Mobilizes bone calcium by stimulating bone resorption. Increases renal absorption of calcium. Decreases renal absorption of phosphate. Increases synth. of calcitriol ® intest. absorption of calcium and phosphate. Net result = calcium, ¯¯phosphate.
Absorption: Dist.: Metabolism.: Inactivated by proteolysis.
Excretion, t½: Minutes.
Toxicity/S.E.s:
Utility: Only used for differential diagnosis—hypoparathyroidism vs. pseudohypoparathyroidism. There is less of an increase in urinary cAMP and phosphate in pseudohypoparathyroidism.
Special Features: Consists of active portion of PTH (1st 34 AAs on N-terminal). Not used to treat hypoparathyroidism. Currently being investigated for treatment of osteoporosis. Intermittent therapy ® anabolic effects on bone.