Prolonged sleep (lat. somnus prolongatus) is a sleep disorder characterized by increased sleep duration.
With this disorder, a person sleeps 10-12 hours a day, and sometimes more. Waking up after such a long sleep is difficult; a person feels very sleepy during the day. There is a slowdown in thought processes, decreased attention and memory. In severe forms, hallucinations may occur.
The reasons for prolonged sleep may be associated with disorders of the brain. Risk factors include traumatic brain injuries, infectious diseases, and brain tumors. Also, prolonged sleep can be a consequence of depression, chronic stress, and disturbances in circadian rhythms.
Diagnosis includes medical history, analysis of a sleep diary, MRI and EEG of the brain. Treatment is aimed at eliminating the underlying disease and normalizing the sleep-wake cycle.