Hypersomnia - idiopathic; Drowsiness - idiopathic; Somnolence - idiopathic
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:
- Feeling irritated
- Loss of appetite
- Low energy
- 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.
Review Date: 06/10/2011
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.