Xywav: A Treatment Option for Idiopathic Hypersomnia in Down Syndrome.

Idiopathic hypersomnia (IH) is a rare and chronic neurological sleep disorder in which patients experience excessive daytime sleepiness (EDS) with symptoms often overlapping with numerous other sleep conditions. This diagnostic overlap can further delay accurate diagnosis and treatment, which poses significant challenges for both patients and clinicians. Additionally, vulnerable populations, such as those with Down syndrome (DS), face further obstacles given the absence of therapeutic studies addressing IH in DS. This case presentation highlights the case of a 40-year-old female patient with DS who suffered from substantial hypersomnolence and had responded favorably to a supervised trial of Xywav (calcium, magnesium, potassium, or sodium oxybates), making this the first known case presentation to demonstrate an effective treatment strategy for this population.