A pharmacodynamic study of desmopressin in patients with nocturnal enuresis

The pharmacokinetics of desmopressin (1-desamino-8-D-arginine vasopressin) were investigated in 8 patients with nocturnal enuresis, of whom 4 were known to respond completely to desmopressin and 4 were nonresponders. A decrease in urine production was confirmed in responders after the administration of desmopressin while the drug did not cause antidiuresis in nonresponders. Absorption and excretion of desmopressin were identical in each group. Results indicate at least 2 pathophysiological mechanisms in nocturnal enuresis, including insufficient nocturnal production of arginine vasopressin and impaired renal sensitivity to arginine vasopressin and desmopressin. Each type results in high nocturnal urine production.