Narcolepsy is a sleep disorder that disrupts the normal sleep-wake cycle. It is a chronic neurological condition in which a person experiences uncontrollable sleepiness, falling asleep, or napping throughout most days. Although this excessive sleepiness usually occurs on a daily basis, it must occur at least three times a week for at least three months to warrant a diagnosis of narcolepsy.
According to the Narcolepsy Network, this condition affects approximately 1 in 2,000 people in the United States, though many go undiagnosed. Narcolepsy typically first develops in children and young adults and rarely makes a first appearance in older adults. The severity of symptoms may change over time, but narcolepsy is a chronic, lifelong condition once symptoms emerge.