Sleepiness and lack of energy aren’t the same thing, reports Cleveland Clinic Health Essentials.

Narcolepsy is a disorder of sleep-wake control — sleep intrudes into wakefulness and waking intrudes into sleep. There are specific signs that point to narcolepsy:

  • Excessive daytime sleepiness. Many people with narcolepsy are unable to stay awake and alert during the day. There are times when they have an irrepressible need for sleep, or unintended lapses into sleep. This is more severe at times and is more likely to happen when you’re sedentary or in a boring or monotonous situation, such as when you’re watching TV or driving a vehicle.