Wernicke's encephalopathy induced by tolazamide

The Wernicke-Korsakoff syndrome is a nutritional neurologic disorder that is due to thiamine deficiency. Although Wernicke's encephalopathy represents the acute phase of the syndrome, Korsakoff's psychosis represents its chronic continuum. Thiamine is a cofactor in glucose metabolism in the glycolytic and pentose phosphate pathways, and a state of thiamine deficiency is well known to be exacerbated or even precipitated by the administration of a glucose load in the patient with marginal thiamine reserves. The correction of hyperglycemia by hypoglycemic agents in diabetic patients increases short-term use of glucose in the tissues, which results in an obligatory demand for more thiamine. Therefore, such agents may also precipitate thiamine depletion and induce Werhicke's encephalopathy in the susceptible patient who has borderline thiamine reserves. The present report describes such a case, evidently caused by use of the hypoglycemic agent tolazamide (Tolinase).