Narcolepsy Symptoms: Excessive Daytime Sleepiness
Reviewed by: HU Medical Review Board | Last reviewed: August 2021 | Last updated: April 2023
Everyone with narcolepsy has excessive daytime sleepiness (EDS). In fact, it is the most recognizable symptom of narcolepsy. EDS means that a person gets sleepy during the day, even though they are getting enough sleep at night.1
People with narcolepsy usually feel rested and alert when they first wake up. However, a person with narcolepsy falls asleep quickly and cannot control it. These are often called “sleep attacks.” These attacks can happen several times a day when the person is in the middle of an activity like eating or talking. In between sleep attacks, the person is alert.
What is the difference between EDS and fatigue?
Excessive daytime sleepiness is often confused with fatigue, another common symptom of sleep disorders like narcolepsy. Fatigue is feeling tired because of illness or a physical activity like exercise or yard work. People with fatigue are not necessarily drowsy.2
Excessive daytime sleepiness means you feel drowsy or sluggish, or cannot keep yourself awake. EDS can make it hard to concentrate and slow your reaction times. In the case of narcolepsy, sudden sleep attacks can be a safety issue.
Why does EDS occur?
People with narcolepsy may have sleep attacks during the day, but the total amount of sleep they get in a 24-hour day is the same as other people. Their sleep just tends to be broken into smaller chunks throughout that 24 hours.3
Doctors believe EDS occurs in people with narcolepsy for two main reasons:3
- They have low levels of the brain chemical hypocretin which controls waking and sleeping.
- Fragmented sleep, meaning the person wakes up several times at night. This causes their sleep quality to be lower.
How is EDS diagnosed?
As part of diagnosing narcolepsy, your doctor will want to measure your daytime sleepiness levels. This information will come from several sources, such as:1,4
- Your medical history
- Sleep diary
- Multiple sleep latency test
- Epworth Sleepiness Scale or Swiss Narcolepsy Scale
How is EDS treated?
The excessive daytime sleepiness of narcolepsy can be treated using a combination of lifestyle changes and medications. Many people with narcolepsy find that a 15- to 20-minute nap keeps them alert for the next 1 to 2 hours. Other than short day-time naps, treatment may include:1,5,6
- Developing good sleep habits
- Stimulants to keep you awake during the day or during important activities like driving and test-taking
- Sodium oxybate (XyremⓇ or XywavⓇ) at night
- Avoiding certain drugs that increase sleepiness, such as cold medicines
- Regular exercise
- Making sure you get enough sleep at night
- Avoiding smoking and alcohol
A narcolepsy service dog may also help the person with narcolepsy cope with sleep attacks.