Update on the treatment of idiopathic hypersomnia: Progress, challenges, and expert opinion

Abstract

Idiopathic hypersomnia is a central hypersomnolence disorder of unknown origin characterized by excessive daytime sleepiness despite normal or long sleep time, and frequent severe sleep inertia. Management strategies have been largely derived from expert consensus, due to a lack of disease-specific assessments and reliance on case series and rare randomized controlled studies. Guidelines recommend treatment with off-label medications. Modafinil, which was approved for idiopathic hypersomnia until 2011 in Europe, is the most commonly used treatment and improved sleepiness in two recent randomized placebo-controlled trials. In 2021, low-sodium oxybate (LXB) was approved in the United States for idiopathic hypersomnia. In a placebo-controlled, double-blind, randomized withdrawal study, LXB reduced daytime sleepiness and sleep inertia, and improved daily functioning. Here, treatment options are reviewed considering the authors' professional experience, current guidelines, and the latest research developments. The choice of pharmacotherapy should be guided by symptom profile, age, comorbidities (eg, depressive symptoms, cardiovascular problems), and concomitant medications (eg, oral contraceptives). Nonpharmacologic approaches have a role in management. An instrument (idiopathic hypersomnia severity scale) has been validated in idiopathic hypersomnia specifically, opening a path to better assessment of symptoms, impact, and response to treatment. Continued research on idiopathic hypersomnia is needed to support treatment algorithms.

Keywords: Efficacy; Excessive daytime sleepiness; Hypersomnolence; Idiopathic hypersomnia; Management; Pharmacotherapy; Safety; Sleep inertia; Treatment.