Signs and symptoms
... The signs and symptoms of narcolepsy include: Excessive daytime sleepiness. The primary characteristic of narcolepsy is overwhelming drowsiness and an uncontrollable need to sleep during the day. Peop...

Causes
... Research continues to determine the cause of narcolepsy. Genetics and some sort of trigger, such as a virus, may affect brain chemicals and contribute to the disorder. The normal process of falling as...

Risk factors
... Narcolepsy affects males and females equally and occurs in all racial and ethnical groups. The condition may run in families. A small percentage of people with narcolepsy have a close relative with th...

When to seek medical advice
... See your doctor if you experience excessive daytime sleepiness that seriously disrupts your personal or professional life.

Screening and diagnosis
... Your doctor may make a preliminary diagnosis of narcolepsy based on your experience of both excessive daytime sleepiness and sudden loss of muscle tone (cataplexy). After an initial diagnosis, your do...