Narcolepsy presenting as schizophrenia: a literature review and two case reports

Schizophrenia is a psychiatric disorder that causes significant disability and morbidity. Narcolepsy is a disorder, less prevalent than schizophrenia, but a disorder in which symptoms overlap with schizophrenia. This overlap in symptoms can cause narcolepsy to be confused with schizophrenia. The differences and similarities between narcolepsy and schizophrenia are discussed in the context of two cases. The first case describes an adolescent and the second case describes a refractory case of narcolepsy that did not respond to stimulants. Both cases were previously diagnosed as schizophrenia and did not respond to trials of antipsychotics and other psychotropics. The patients were reevaluated and referred to sleep testing at our facility for clinical suspicion of narcolepsy. Both patients underwent polysomnography with subsequent multiple sleep latency testing. The sleep testing results and multiple sleep latency testing criteria for narcolepsy are also discussed. The patients were treated for narcolepsy resulting in remission of the psychotic symptoms with significant behavioral improvement. We recommend that psychiatrists consider narcolepsy in the differential diagnosis when faced with refractory psychosis.