Millions of people have experienced sleeprelated concerns, and millions more suffer from serious sleeping disorders. The lack of proper rest can lead to fatigue at work, affect alertness while driving as well as other serious physical and mental health problems. Written for both the lay reader and the professional, The Encyclopedia of Sleep and Sleep Disorders describes the important terms and topics related to sleep research and disorder treatment.

Since the first edition of The Encyclopedia of Sleep and Sleep Disorders was published in 1991, there has been a great expansion in the national awareness of sleep disorders and an increase in services for patients. Terms such as narcolepsy, insomnia, sleep apnea and excessive daytime sleepiness are commonly used and understood by a greater percentage of the population than before. Laypersons have become more aware that there is help available if they suffer from a sleep disorder. This increased awareness is a positive development. Better understanding of the symptoms and features of a sleep disorder leads to more rapid recognition and treatment of the disorder.

The Encyclopedia of Sleep and Sleep Disorders has been updated to reflect the current science and understanding of sleep disorders and includes the addition of numerous entries that reflect new terms, drugs and procedures introduced in the last decade. Recent advances in the understanding of the pathophysiology of sleep and wakefulness, including the recognition of a neurochemical system involved in the control of sleep and wakefulness, the orexin system, are covered in this second edition. Revised entries reflect the advances in our understanding and treatment of disorders such as sleep apnea, insomnia and narcolepsy. Modafinil, recently approved in the United States, is a major breakthrough medication for the treatment of disorders of tiredness, fatigue, sleepiness and narcolepsy. This medication is being used to treat obstructive sleep apnea syndrome and other disorders that produce tiredness and fatigue, such as multiple sclerosis.