Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 25-15: Sleep-Wake Disorders + Key Features Download Section PDF Listen +++ ++ A disorder of excessive sleepiness, manifesting in "sleep attacks" Disorder begins in early adult life Affects both sexes equally Severity levels off at ~30 years of age + Clinical Findings Download Section PDF Listen +++ ++ Tetrad of symptoms Sudden, brief sleep attacks during any type of activity Cataplexy, a loss of specific or generalized muscle tone Sleep paralysis: a flaccidity of muscles with full consciousness while falling or waking from sleep Hypnagogic hallucinations, preceding sleep or occurring during a sleep attack + Diagnosis Download Section PDF Listen +++ ++ Sleep study Attacks are characterized by abrupt transition into REM sleep, a necessary criterion for diagnosis + Treatment Download Section PDF Listen +++ ++ Dextroamphetamine, 10 mg orally each morning Modafinil, 200 mg orally each morning Mechanism of action is unknown, but risk of abuse is thought to be lower than with stimulants May reduce the efficacy of cyclosporine, oral contraceptives, and other medications by inducing their hepatic metabolism Common side effects include headache and anxiety Imipramine, 75–100 mg once daily orally, is effective in treatment of cataplexy but not narcolepsy