Abstract
We reported a 6-year-old girl with Rett syndrome with severe apnea attacks following hyperventilation during wakefulness for which oral diazepam, 1.5mg per day, showed marked effect. We evaluated the efficacy of diazepam by polysomnography. Polygraphical examinations revealed decrease of apnea attacks from 15.7/hour to 0.6/hour and of the duration of the longest apnea attack from 40 seconds to 18 seconds. The seresults support the previous reports which suggests involvement of the cerebral cortex and the reticular formation for respiratory disturbance in Rett syndrome.