Narcolepsy: current treatment options and future approaches

Abstract

The management of narcolepsy is presently at a turning point. Three main avenues are considered in this review: 1) Two tendencies characterize the conventional treatment of narcolepsy. Modafinil has replaced methylphenidate and amphetamine as the first-line treatment of excessive daytime sleepiness (EDS) and sleep attacks, based on randomized, double blind, placebo-controlled clinical trials of modafinil, but on no direct comparison of modafinil versus traditional stimulants. For cataplexy, sleep paralysis, and hypnagogic hallucinations, new antidepressants tend to replace tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs) in spite of a lack of randomized, double blind, placebo-controlled clinical trials of these compounds; 2) The conventional treatment of narcolepsy is now challenged by sodium oxybate, the sodium salt of gammahydroxybutyrate, based on a series of randomized, double-blind, placebo-controlled clinical trials and a long-term open label study. This treatment has a fairly good efficacy and is active on all symptoms of narcolepsy. Careful titration up to an adequate level is essential both to obtain positive results and avoid adverse effects; 3) A series of new treatments are currently being tested, either in animal models or in humans, They include novel stimulant and anticataplectic drugs, endocrine therapy, and, more attractively, totally new approaches based on the present state of knowledge of the pathophysiology of narcolepsy with cataplexy, hypocretine-based therapies, and immunotherapy.