Acute aquaresis by the nonpeptide arginine vasopressin (AVP) antagonist OPC-31260 improves hyponatremia in patients with syndrome of inappropriate secretion of antidiuretic hormone (SIADH)

J Clin Endocrinol Metab. 1997 Apr;82(4):1054-7. doi: 10.1210/jcem.82.4.3900.


The present study was undertaken to determine whether the non-peptide V2 arginine vasopressin (AVP) antagonist 5-dimethylamino- 1[4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-benzazepi ne hydrochloride (OPC-31260) produces water diuresis and improves hyponatremia in patients with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Eleven patients (9 males and 2 females, 64 +/- 3.5 yr) with SIADH were included in the present protocol, which was comprised of 3 successive days. Day 1 was a control day, and on days 2 and 3 OPC-31260 was administered intravenously. Five blood and urine collections were made at 1-2 h intervals during the 6 h observation period each day. A single administration of 0.25 and 0.5 mg/kg OPC-31260 increased the 4 h cumulative urine volume and decreased urinary osmolality to below 225 mOsm/kg H2O. Such a diuretic effect was independent of an increase in urinary solute excretions. This aquaresis by 0.5 mg/kg OPC-31260 caused a significant increase in serum sodium level by approximately 3 mEq/L. The antagonistic effect of OPC-31260 lasted for 4 h when it was given intravenously. These results indicate that OPC-31260 is an effective therapeutic agent for hyponatremia in patients with SIADH.

Publication types

  • Clinical Trial

MeSH terms

  • Aged
  • Arginine Vasopressin / antagonists & inhibitors*
  • Benzazepines / therapeutic use*
  • Diuresis
  • Diuretics / therapeutic use*
  • Female
  • Humans
  • Hyponatremia / blood
  • Hyponatremia / drug therapy*
  • Hyponatremia / urine
  • Inappropriate ADH Syndrome / blood*
  • Male
  • Middle Aged
  • Osmolar Concentration
  • Sodium / blood
  • Treatment Outcome
  • Urine / chemistry


  • Benzazepines
  • Diuretics
  • Arginine Vasopressin
  • mozavaptan
  • Sodium