Delayed sleep-wake phase disorder.

One of seven circadian rhythm disorders, delayed sleep-wake phase disorder (DSWPD) commonly occurs in adolescents and young adults. The disorder is frequently confused with insomnia and can be a presenting complaint, as the individual is often stressed about being unable to fall asleep at the desired time. The underlying disruption occurs due to a shift between when the individual wants to sleep and when the individual can. Unlike patients with insomnia, patients with DSWPD can achieve sleep easily at later times, leading to later wake-up times. The inability to adapt to the societal norm in terms of the standard school, work, or social schedule leads to stressors, further complicating the disorder. Sleep questionnaires, sleep diaries, and actigraphy have improved identification of individuals with delayed sleep. Treatment of DSWPD involves the use of scheduled melatonin, scheduled sleep-wake times, and bright light therapy. If identified early, the disorder can be successfully managed.