Absorption Subcutaneous administration of<unk>  hormone into the abdomen produces a rapid increase in plasma<unk>  hormone levels which reach peak at 1 to 2 hours after dosing. The mean half-life is approximately 1.5 hours. The absolute bioavailability of 100 micrograms of Preotact after subcutaneous administration in the abdomen is 55%. Distribution The volume of distribution at steady-state following intravenous administration is approximately 5.4 liters. Intersubject variability is about 40%. Biotransformation<unk>  hormone is efficiently removed from the blood by a receptor-mediated process in the liver and is broken down into smaller peptide fragments. The fragments derived from the amino-terminus are further degraded within the cell while the fragments derived from the carboxy-terminus are released back into the blood and cleared by the kidney. These carboxy-terminal fragments are thought to play a role in the regulation of<unk>  hormone activity. Under normal physiological conditions full-length<unk>  hormone H constitutes only 5-30% of the circulating forms of the molecule, while 70-95% is present as carboxy-terminal fragments. Following administration of Preotact, carboxy-terminal fragments make up about 60-90% of the circulating forms of the molecule. Intersubject variability in systemic clearance is about 15%. Elimination<unk>  hormone is metabolised in the liver and to a lesser extent in the kidney. It is not excreted from the body in its intact form. Circulating carboxy-terminal fragments are filtered by the kidney, but are subsequently broken down into even smaller fragments during tubular reuptake. No studies have so far been performed in patients with severe hepatic impairment. The pharmacokinetics of<unk>  hormone in patients with severe chronic kidney disease (creatinine clearance of less than 30 ml/min) has not been investigated either.
Recombinant human parathyroid hormone
Streptozotocin
Parathyroid hormone
Calcipotriol
Parathyroid hormone-related protein
Parathyroidectomy
Calcitriol
Calcium/cholecalciferol