RESUMO
Wernicke's encephalopathy is an acute neurological syndrome due to thiamine deficiency, which is characterized by a typical triad of mental status changes, oculomotor dysfunction and ataxia. Despite the fact that Wernicke's encephalopathy, in developed countries, is frequently associated with chronic alcoholism, there have been a number of published cases associating this encephalopathy with parenteral feeding without vitamin supplementation. Diagnosis is primarily a clinical one, and can be supported by laboratory tests and imaging studies; treatment should start as soon as possible, for the morbidity and mortality (almost 20%) associated with this syndrome is high. Thiamine supplementation, along with other vitamins, is recommended for patients in risk of developing this syndrome.