Idiopathic hypersomnia is sleeping too much (hypersomnia) without an obvious cause. It is different from narcolepsy, because idiopathic hypersomnia does not involve suddenly falling asleep or losing muscle control due to strong emotions (cataplexy).
Symptoms often develop slowly during adolescence or young adulthood. They include:
Daytime naps that do not relieve drowsiness
Difficulty waking from a long sleep -- may feel confused or disoriented
Increased need for sleep during the day -- even while at work, or during a meal or conversation
Increased sleep time -- up to 14 - 18 hours per day
Other symptoms may include:
Anxiety
Feeling irritated
Loss of appetite
Low energy
Restlessness
Slow thinking or speech
Trouble remembering
Cataplexy -- suddenly falling asleep or losing muscle control -- which is part of narcolepsy, is NOT a symptom of idiopathic hypersomnia.
Signs and tests
The health care provider will take a detailed sleep history. Tests may include:
Multiple-sleep latency test
Sleep study (polysomnography, to identify other sleep disorders)
A psychiatric evaluation for atypical depression may also be done.
Treatment
Idiopathic hypersomnia is usually treated with stimulant medications such as amphetamine, methylphenidate, and modafinil. These drugs may not work as well for this condition as they do for narcolepsy.
Important lifestyle changes that can help ease symptoms and prevent injury include:
Avoiding alcohol and medications that can make the condition worse
Avoiding operating motor vehicles or using dangerous equipment
Avoiding working at night or social activities that delay bedtime
Review Date:
6/10/2011
Reviewed By:
Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
