Narcolepsy and psychosis; case report.

Narcolepsy is an infrequent neurological disorder, included in the catalog of rare diseases. Despite the existenceof precise diagnostic criteria, this entity remains underdiagnosed. It is characterized by excessive daytime sleepiness associated with cataplexy; in some cases, hypnagogic or hypnopompic hallucinations, auditory hallucinations, and/or delusional ideation may appear. The occurrence of psychotic symptoms makes differential diagnosis extremely difficult (narcolepsy, schizophrenia, or both). Furthermore, therapeutic management may be complex, since the treatment of one of the disorders may worsen the other. Here we describe the case of a patient with this rare comorbidity, which illustrates the major difficulties associated to both differential diagnosis and therapeutic management once a definitive diagnosis has been reached.