Insomnia Basics:

Insomnia, which is Latin for "no sleep," is the inability to fall asleep or remain asleep. Insomnia is also used to describe the condition of waking up not feeling restored or refreshed. According to Dr. MarkMahowald, Professor of Neurology at the University of Minnesota Medical School and Director of the Minnesota Regional Sleep Disorders Center at Hennepin County Medical Center, insomnia refers to the inability to get the amount of sleep you as an individual need to wake up feeling rested.

Insomnia is the most common sleep complaint among Americans. According to the National Institutes of Health, insomnia affects more than 70 million Americans. It can be either acute, lasting one to several nights, or chronic, even lasting months to years. When insomnia persists for longer than a month, it is considered chronic. According to sleep specialist Dr. William Dement, Director of the Sleep Disorders Clinic and Laboratory at the Stanford University School of Medicine, people who have trouble sleeping every night without exception for months or years are fairly rare. More often, people experience chronic-intermittent insomnia, which means difficulty sleeping for a few nights, followed by a few nights of adequate sleep before the problem returns.

Insomnia can be a disorder in its own right, but often it is a symptom of some other disease or condition. Half of all those who have experienced insomnia blame the problem on stress and worry. In the case of stress-induced insomnia, the degree to which sleep is disturbed depends on the severity and duration of the stressful situation. Sometimes this may be a disturbing occurrence like loss of a loved one, loss of a job, marital or relationship discord or a tragic occurrence. Anticipation of such things as weddings, vacations, or holidays can also disturb sleep and make it difficult to fall asleep or remain asleep. Insomnia can also occur with jet lag, shift work and other major schedule changes.

If you have difficulty sleeping, it is essential to determine whether an underlying disease or condition is causing the problem. Sometimes insomnia is caused by pain, digestive problems or a sleep disorder. Insomnia may also signal depression or anxiety. Often times, insomnia exacerbates the underlying condition by leaving the patient fatigued and less able to cope and think clearly. For insomnia related to a medical condition or pain, ask your doctor about nighttime pain aids.

If your sleep trouble is confined to difficulty falling asleep, the time you are choosing to go to sleep may not be synchronized with your biological clock. The biological processes that initiate and maintain sleep in humans are active throughout the night. Opposing this sleep tendency, however, is the alerting action of the biological clock that is active throughout the day. When the biological clock is active at your scheduled bedtime, you will have sleep-onset insomnia.

The prevalence of insomnia is higher among older people and women. Women suffer loss of sleep in connection with menstruation, pregnancy, and menopause. Rates of insomnia increase as a function of age but most often the sleep disturbance is attributable to some other medical condition. See also "Aging."

Some medications can lead to insomnia, including those taken for:* colds and allergies
* high blood pressure
* heart disease
* thyroid disease
* birth control
* asthma
* pain medications
* depression (especially SSRI antidepressants)

Some common sleep disorders such as restless legs syndrome and sleep apnea can also lead to insomnia.

Sleep is as essential as diet and exercise. Inadequate sleep can result in fatigue, depression, concentration problems, illness and injury.

Reviewed by Dr. David Neubauer

© National Sleep Foundation