The usual signs and symptoms of hypoglycemia include tachycardia and profound diaphoresis. These will progress to include an altered mental status that can advance in severe cases to coma, seizures, and death. Occasionally, hypoglycemia may present with focal neurologic signs that can include hemiparesis or hemiplegia with preservation of mental status. In patients with the latter signs, the possibility of a cerebrovascular accident or other intracranial abnormality must be considered. The authors describe an elderly patient with hypoglycemic hemiplegia secondary to insulin administration. Their report includes observations on clinical presentation, the various mechanisms involved, and guidelines for the management of this syndrome.