We described the case of a young man with morbid obesity who underwent bariatric surgery who experiences different complications. After the discharge the patient starts to complain about nausea, dizziness, and visual impairment. After a first access to an emergency department, with a diagnosis of labyrinthopathy, the patient gets worse. He then has been hospitalized and a wernicke's encephalopathy was diagnosed. During the hospitalization other comploication of low thiamine appeared such as wet beriberi. The clinical picture was also complicated with the refeeding syndrome. Wernicke's encephalopathy, wet beriberi, and refeeding syndrome are life-threatening conditions that can be prevented and treated. Both physicians and patients must be warned about these potential risks in order to put in act a prompt treatment.