Treatment options in narcolepsy

Abstract

Introduction: Narcolepsy is a rare disorder classified as hypersomnia of central origin. Its core symptoms are excessive daytime sleepiness (EDS) and cataplexy. Associated symptoms, hypnagogic hallucinations, sleep paralysis, automatic behavior, and sleep fragmentation, are unspecific. Genetic, autoimmune, and environmental factors contribute to hypocretin deficiency.

Areas covered: This article focuses on therapies for narcolepsy symptoms and comorbid disorders. Despite the enormous increase of knowledge about narcolepsy's pathologies no substance has been developed that can cure the disease. So far hypocretin substitution is not available. Substances targeting the autoimmune mechanism have failed to show objective improvement despite subjective improvement. The standard medication in adults comprises stimulants and anticataplectics. Only few substances are capable of improving core and associated symptoms. Within the last years, only modafinil and its enantiomer armodafinil and sodium oxybate have been approved as new substances.

Expert opinion: The choice of stimulants to treat excessive daytime sleepiness in narcolepsy needs to be expanded and anticataplectic medication needs to be approved for the indication. Head-to-head comparisons between the established medications, studies of high evidence in older non-evidence-based medications, in children, pregnant women, and of behavioral therapy need to be performed including the long-term effects on metabolic and cardiovascular risks. Narcolepsy is a model disease for so many sleep disorders, among which it has the most severe daytime sleepiness. New insights into its etiology have advanced sleep medicine immensely. Still it stays an orphan in terms of treatment options which are challenging because narcolepsy covers so many symptoms from neuropsychological metabolic-, cardiovascular-, endocrinological-, movement disorders, and parasomnias to name a few.

Keywords::

• antidepressants
• autoimmunity
• cataplexy
• excessive daytime sleepiness
• genetics
• hypocretin
• narcolepsy
• stimulants

Declaration of interest

G Mayer has received speaker's honoraria and travelling expenses for conferences from UCB Pharma, Genzyme, Desitin, Lilly, and Cephalon. He has participated on advisory boards for UCB Pharma and Genzyme. His research has been supported by grants of UCB Pharma and Cephalon. Y Dauvilliers has received speaker's honoraria and travelling expenses for conferences from UCB Pharma, Jazz, and Bioprojet. He has participated on advisory boards for UCB Pharma, Jazz, and Bioprojet. C Bassetti has received over the last 2 years honoraria for consultancy, lectures, and board memberships from the following companies: Bayer, Boehringer Ingelheim, Cephalon, GSK, Jazz, Lundbeck, Medtronic, Pfizer, ResMed, Respironics, UCB Pharma, Vifor Pharma, Swiss Neurological Society. His research is currently supported by grants of the Swiss National Science Foundation, Respironics, Vifor Pharma, and UCB Pharma.

Notes

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