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Hypersomnia / Daytime Sleepiness Directory
Hypersomnia/daytime sleepiness is episodes of excessive sleepiness during the day. Follow the links below to find WebMD's comprehensive coverage about how hypersomnia/daytime sleepiness occurs, how it's diagnosed, how to treat it, and much more.
Medical Reference
Symptoms of Narcolepsy
WebMD provides an overview of narcolepsy, including symptoms and treatment.
Basics on Sleep
WebMD explains the stages of sleep -- REM and non-REM -- and how age affects these cycles.
Sleep and Hypersomnia
WebMD looks at the condition called hypersomnia, characterized by excessive daytime sleepiness.
Diagnosing Narcolepsy
A diagnosis of narcolepsy requires a few tests. WebMD explains what they are and how they are performed.
Features
You May Have a Chronic Sleep Disorder If …
Wake up to this simple fact: You are not supposed to be sleepy, with your feet draggin' and lids laggin' during the day.
The Toll of Sleep Loss in America
Sleep loss is taking a toll on our physical and emotional health, and on our nation's highways.
Why Am I Always So Tired?
Learn about conditions that might cause you to feel sluggish during the day, such as anemia, thyroid trouble, sleep apnea, diabetes, heart disease, depression, and menopause.
The Best Mattress for a Good Night's Sleep
Buying a new mattress? Experts offer their tips for choosing the right mattress so you can sleep better.
Video
Slideshows & Images
Slideshow: Fighting Fatigue and Sleepiness on the Road
Fighting Fatigue and Sleepiness on the Road
See the surprising dangers of driving sleepy. Learn what increases your risk of a car accident and tips to keep you safe whether it is insomnia, narcolepsy, or something else making you tired.
A Visual Guide to Sleep Disorders
Pictures show you the symptoms, causes, tests, and treatments for sleep problems.