Medical Terminology

idiopathic hypersomnia (IH)

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Idiopathic hypersomnia (IH) is a neurological disorder characterized by excessive daytime sleepiness (often with associated cognitive dysfunction), despite getting a full night’s sleep or longer. People with IH may also experience difficulty awakening, sleep drunkenness, automatic behaviors, and symptoms related to the autonomic nervous system, such as feeling lightheaded when standing up quickly. Read more About IH.