Cerebral autoregulation is the mechanism by which constant cerebral blood flow is maintained despite changes in arterial blood pressure. In the two presented cases, cerebral autoregulation was impaired in patients with narcolepsy type 1, and both venlafaxine and fluoxetine may have the potential to improve the impaired cerebral autoregulation. A relationship may exist between impaired cerebral autoregulation and neurological symptoms in patients with narcolepsy type 1.