Antidiuretic effect of perorally administered DDAVP in hydrated humans

Urine volume and osmolality were measured in volunteers hydrated with drinking water (2% of body weight). During maintained water diuresis DDAVP (1-deamino-8-D-arginine vasopressin) dissolved in water was administered per os. Within 15-30 min a dose-dependent antidiuretic response occurred with a concomitant increase in urine osmolality. Administration of DDAVP through a duodenal tube caused similar antidiuretic effects indicating that the intact peptide can be absorbed from the intestinal mucosa.