Primary Hypersomnia : Response to Fluoxetine and Methylphenidate

Primary hypersomnia, a rare clinical syndrome, was diagnosed in a 14-year-old boy. The syndrome showed partial response to high dose fluoxetine therapy (120 mg/day) which recruited insomnia, an adverse effect of the drug, for therapeutic purposes. Response was enhanced with intermittent methylphenidate in association with a lower dose of fluoxetine. A possible pharmacokinetic interaction developed, comprising fluoxetine-induced augmentation of methylphenidate activity; such an interaction has not been previously reported.