Delayed sleep phase disorder (DSPD) is a circadian
rhythm sleep disorder. Patients with DSPD have problems initiating
sleep if they go to bed at a conventional time and they have serious
problems waking up at desired times. The disorder is most common
among adolescents. Many of the patients struggle with school
attendance, and school grades deteriorate. Furthermore, studies
show that DSPD is associated with smoking, alcohol usage, anxiety
and depression. The recommended treatment options are bright light
and exogenous melatonin