Abstract
Narcolepsy with cataplexy (NT1) is a sleep disorder very rarely associated with early-onset psychosis. The incidence of this association is unknown but appears to be more common in children and adolescents. This combination of diagnoses presents a diagnostic and therapeutic challenge. This case report discusses an adolescent female with first-episode psychosis who was being treated for NT1 and had no prior psychiatric history. After ruling out other possible medical causes, she was given an initial diagnosis of a brief psychotic episode and treated with Risperidone while continuing treatment for NT1 with Modafinil and Venlafaxine. Following partial response to Risperidone, her psychosis improved with Chlorpromazine, one of the first documented cases of successful use of this medication for first-episode psychosis with NT1.