Hypoglycemia associated with phenytoin intoxication

Background: Diphenylhydantoin, a widely used antiepileptic agent, can alter carbohydrate tolerance, and acute intoxication with diphenylhydantoin can be associated with hyperglycemia. Case Report: We describe a patient who experienced a prolonged episode of hypoglycemia secondary to an acute voluntary intoxication with diphenylhydantoin 20 g and zopiclone 225 mg. This hypoglycemic episode was presumptively attributed to diphenylhydantoin and might be due either to an escape from the inhibitory effects of diphenylhydantoin on insulin secretion or an increased sensitivity of the tissues to insulin. Zopiclone was considered less likely since zopiclone overdoses have been only exceptionally associated with hyperglycemia.