define narcolepsy

Narcolepsy is a neurological sleep disorder characterized by excessive daytime sleepiness, sudden and uncontrollable sleep attacks, and disruptions in sleep cycles. People with narcolepsy may also experience cataplexy, a sudden loss of muscle tone triggered by strong emotions such as laughter or surprise. Other symptoms may include sleep paralysis, hallucinations, and disrupted nighttime sleep. Narcolepsy is caused by a deficiency of a neurotransmitter called hypocretin in the brain and is typically treated with medication and lifestyle changes