Lithium carbonate treatment in the syndrome of inappropriate secretion of antidiuretic hormone.

A case of a 76-year-old man with the syndrome of inappropriate secretion of antidiuretic hormone (ADH) is discussed. The patient was initially treated with fluid restriction followed by the administration of hypertonic saline. After failure to achieve rapid correction of the condition and continued lethargy and muscle weakness in the patient, a trial with lithium carbonate 300 mg three times daily via nasogastric tube was initiated. This resulted in a prompt reversal of the hyperosmolar state and improvement in electrolyte balance. However, despite the apparent success in treating his inappropriate ADH, the patient expired as a result of a massive cerebral vascular accident. The potential benefit of using lithium in the treatment of the syndrome of inappropriate secretion of ADH, and possible mechanisms of action, are reviewed.