Acute bilateral ophthalmoplegia in a young woman

A 34-year-old woman presented with bilateral ophthalmoplegia, ptosis, and mild gait ataxia. Tensilon test, magnetic resonance imaging, and cerebrospinal fluid analysis were normal. She initially denied any alcohol intake but later admitted to significant alcohol and multisubstance abuse. The patient improved dramatically after treatment with thiamine. Wernicke's encephalopathy is discussed, highlighting that it may be present with normal mentation. It should be considered in the differential diagnosis of bilateral ophthalmoplegia even in the absence of altered mental status.