Idiopathic hypersomnia
Definition
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).
Alternative Names
Hypersomnia - idiopathic; Drowsiness - idiopathic; Somnolence - idiopathic
Causes
The usual approach is to consider other potential causes of excessive daytime sleepiness.
Other sleep disorders that may cause daytime sleepiness include:
Other causes of excessive sleepiness include:
Symptoms
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.
Exams 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
References
Consens FB, Chervin RD. Sleep Disorders. In: Goetz, CG, ed. Textbook of Clinical Neurology. 3rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 54.
Tsai SC. Excessive sleepiness. Clin Chest Med. 2010; 31:341-351.
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.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-
A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
