Wernicke’s syndrome is a type of brain disorder that is caused by a long-term, inefficient amount of vitamin B1 (thiamine). It is also known as Wernicke's encephalopathy or Wernicke-Korsakoff syndrome.  The condition most often occurs among people who suffer from alcoholism. However, it can also occur among people who are undergoing chemotherapy treatment, are vomiting chronically, have an eating disorder, or have had bariatric surgery. Wernicke’s syndrome is actually two separate conditions, Wernicke’s encephalopathy and Korsakoff’s syndrome.