Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease of the central nervous system that is associated with significant morbidity and mortality. Early recognition of the disease is of paramount importance; however, treatment options are limited because only case reports and small series are available in the literature. We report a case of a 42 year-old previously healthy man, whom we treated successfully with a combination regimen of methylprednisolone, IV immunoglobulin, and plasmapheresis early in the course of the disease.