Guest Editor's Introduction: Diagnosis and Treatment of Insomniaat the Start of the 21st Century

Insomnia is an important public health problem, yet one often left undiagnosed and, therefore, undertreated. When diagnosing insomnia, a clinician should consider impaired sleep quality and other subjective complaints of the patient as important as reduced sleep quantity. The comprehensive treatment of insomnia should combine general sleep-wake hygiene measures, appropriate psychotherapeutic techniques, and use of hypnotics. Parallel treatment of coexisting mental and physical disorders is of paramount importance. The overall therapeutic approach needs to be individualized. In this respect, dosing flexibility when using hypnotics may contribute not only to more efficient control of sleeplessness but also to prevention of chronic insomnia. Zaleplon, a novel hypnotic agent that can be administered when symptoms occur (i.e., at bedtime or during the night), provides greater versatility of intake than other hypnotics and is expected to facilitate more rational treatment of insomnia.