[Ethanol, water, salt and coma]. / Alkohol, Wasser, Salz und Koma.

We report on a 52-year-old woman with liver cirrhosis who suddenly fell into deep coma after correction of an intercurrent hyponatremia. After exclusion of the commonest causes of coma, the MRI showed a symmetrical osmotic demyelination of both thalami. The newest epidemiological data, the pathophysiology of osmotic demyelination, the threats of the treatment of a prolonged severe hyponatremia as well as the therapeutic options in face of osmotic demyelination are discussed.