Insomnia is a sleep disorder. People with insomnia have trouble sleeping: difficulty falling asleep, or staying asleep as long as desired. While the term is sometimes used to describe a disorder as diagnosed bypolysomnographic or actigraphic evidence, this is often practically defined as a positive response to either of two questions: "do you experience difficulty sleeping?" or "do you have difficulty falling or staying asleep?"
Insomnia is most often thought of as both amedical sign and a symptom that can accompany several sleep, medical, and psychiatric disorders characterized by a long term difficulty falling asleep and/or staying asleep or sleep of poor quality. Insomnia is typically followed by functional impairment while awake. Insomnia can occur at any age, but it is particularly common in the elderly.Insomnia can be short term (up to three weeks) or long term (above 3–4 weeks); it can lead to memory problems, depression, irritability and an increased risk of heart disease and automobile related accidents.
Insomnia can be grouped into primary and secondary insomnia. Primary insomnia is a sleep disorder not due to a medical, psychiatric, or environmental cause. It is described as a complaint of prolonged sleep onset latency, disturbance of sleep maintenance, or the experience of non-refreshing sleep. A diagnosis will differentiate between free-standing primary insomnia, insomnia as secondary to another condition, and primary insomnia co-morbid with one or more conditions.
Cognitive behavioral therapy is useful in insomnia that is present for a long duration. Those who are having trouble sleeping sometimes turn to sleeping pills, which may help, but also may lead tosubstance dependency or addiction, and long-term worsening of sleep, if used regularly for an extended period