Drowsiness refers to feeling excessively tired or sleepy, especially at times when a person would not usually need to sleep. There are several reasons that a person may feel drowsy, and drowsiness may ...

While it’s common to develop some fatigue with age, if you’re seeing sudden or severe exhaustion, see a doctor to rule out an underlying medical cause. If you or your aging parent suddenly can’t get ...

To know whether you have narcolepsy, it's important to recognize a few common symptoms, such as excessive daytime sleepiness.

About 3.3 million U.S. adults have chronic fatigue syndrome, according to new data from the Centers for Disease Control and Prevention. The number is the first nationally representative estimate of ...