DDAVP Subcutaneous Half-Life
The elimination half-life of desmopressin (DDAVP) after subcutaneous administration is approximately 3.1 hours in healthy adults. 1
Pharmacokinetic Profile After Subcutaneous Administration
Peak plasma concentrations of 480-638 pg/ml are reached approximately 1 hour after subcutaneous injection at a dose of 0.4 μg/kg body weight 1
The mean elimination half-life is 3.1 hours following subcutaneous administration, based on direct pharmacokinetic measurements in healthy volunteers 1
After intravenous administration (which provides comparative context), the elimination half-life is 78 ± 10 minutes (approximately 1.3 hours), suggesting subcutaneous administration results in a somewhat longer half-life due to absorption kinetics 2
Duration of Clinical Effect vs. Plasma Half-Life
Important clinical distinction: The plasma half-life does not directly correlate with duration of therapeutic effect:
Hemostatic effects begin within 1 hour and last 6-8 hours after administration, substantially longer than the plasma half-life 3, 4
The antidiuretic effect can persist for up to 12 hours or more after administration, particularly with nighttime dosing 5
This prolonged clinical effect occurs because desmopressin triggers release of stored von Willebrand factor and Factor VIII from endothelial cells, and these factors have their own elimination kinetics (half-lives ranging from 1.3-11.4 hours) 1
Dosing Implications
Doses can be repeated at 12-24 hour intervals for ongoing hemostatic needs, though tachyphylaxis may occur after 3-5 doses due to depletion of endothelial VWF stores 6
The standard subcutaneous dose is 0.3-0.4 μg/kg, which produces therapeutic effects despite the relatively short plasma half-life 6, 3, 4, 1