Hyperemesis gravidarum is a complication of pregnancy associated with severe 
nausea and vomiting that can lead to fluid-electrolyte imbalances and 
nutritional deficiencies. Wernicke's encephalopathy is a neurologic 
manifestation of acute thiamine (vitamin B1) deficiency. We describe a case of 
hyperemesis gravidarum presenting with gait ataxia and nystagmus which led to a 
diagnosis of Wernicke's encephalopathy.