Use of conivaptan for refractory syndrome of inappropriate secretion of antidiuretic hormone in a pediatric patient.

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is the most common form of hyponatremia in hospitalized patients. The available treatment options for SIADH are limited and not completely effective. A more recent and specific option for treatment of hyponatremia secondary to SIADH are the vasopressin-receptor antagonists. Conivaptan, an intravenous vasopressin-receptor antagonist, is Food and Drug Administration approved for the treatment of euvolemic and hypervolemic hyponatremia in adults; however, data regarding its use in pediatric patients are extremely limited. Conivaptan played an integral role in the treatment of hyponatremia in this situation when conventional treatment modalities were ineffective. This patient did not experience any adverse effects, and his sodium level corrected slowly over a 24-hour period, avoiding complications of rapid sodium correction.