Suspected inappropriate secretion of antidiuretic hormone in a male with mental retardation.

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is a disorder in which a sustained release of antidiuretic hormone occurs because of certain diseases, pharmacological agents, or trauma. Fluid volume expands with a resultant hyponatremia which, depending on the degree, may be asymptomatic or result in death. This case report describes a 38-year-old male in whom SIADH was strongly suspected secondary to Tegretol therapy to control a seizure disorder. Medical consultation is imperative for these patients before administering a fluid challenge during general anesthesia.