What is Idiopathic Hypersomnia?

Idiopathic hypersomnia is a medical condition characterized by excessive sleeping without a known cause. The onset of hypersomnia may be due to behavioral or psychological factors or to the presence of a secondary condition. Routine testing may be employed to determine the potential cause or causes for idiopathic hypersomnia. Treatment for this condition generally involves the use of prescription, stimulant medications and the implementation of lifestyle changes to ease symptoms.

Hypersomnia, also known as somnolence or drowsiness, is a feeling of sleepiness that occurs during the daytime. Individuals who develop this condition without a known trigger are considered to have a significant sleep disorder. Common causes for hypersomnia may include the use of certain prescription medications, occupational and environmental stressors, depression, and insufficient rest at night. More serious cases of hypersomnia may be related to the presence of a significant sleep disorder, such as sleep apnea or narcolepsy.

Individuals with idiopathic hypersomnia most frequently require daytime naps, though he or she may not feel rested upon waking. Other signs of this disorder include feelings of confusion or disorientation upon waking from long periods of sleeping, an increased need for sleep and increased sleep time of up to 18 hours a day. Additional symptoms associated with idiopathic hypersomnia include anxiety, weight loss, and impaired cognition and speech.

In order to determine the cause of hypersomnia, routine testing, as utilized to diagnose other sleep disorders, may be conducted. During an initial consultation, a physician may take a detailed medical history and ask several questions about the symptoms an individual may be experiencing. The individual may then be referred for a sleep study, also known as a polysomnography, and a multiple-sleep latency test, which measures how long it takes the individual to fall asleep. Additionally, a psychiatric evaluation may be ordered to rule out the presence of an anxiety disorder or acute depression.

A polysomnography is usually conducted at a sleep study center, administered and monitored by a trained health care technician, and takes place at night to evaluate one’s natural sleep patterns. An individual is usually given his or her own room and electrodes are placed on his or her scalp, chin, and near the eyelids. The sleep study evaluates elements such as an individual’s sleep cycles, body position, and breathing rate. Additional aspects that may be evaluated include the individual's muscular electrical activity and his or her eye movement.

The electrodes remain in place throughout the night so the individual’s breathing and heart rate may be monitored. Signals sent through the electrodes are evaluated for any changes or abnormalities indicative of breathing cessation or near-cessation. Additionally, the individual may be monitored visually with the aid of a video camera that records his or her movements while he or she is asleep.

Individuals, for whom the cause of his or her hypersomnia remains elusive, may be treated with stimulant medications, such as methylphenidate and amphetamine. These drugs work by stimulating the nervous system and increasing one’s blood pressure and heart rate. Used to treat other sleep disorders, such as narcolepsy, these potentially habit-forming drugs should only be used under the supervision of a qualified health care provider. Individuals with pre-existing conditions such as glaucoma, hypertension, and heart disease may be advised to avoid these stimulant medications due to the risk of significant complications, including death.

In addition to the use of a prescription medication, individuals with idiopathic hypersomnia may be encouraged to adopt a sleep schedule to which they should strictly adhere. Avoiding naps during the day and going to bed at the same time every night are habits often suggested to retrain the mind and body and promote a more restful, healthy sleep. Activities that interfere or disrupt an established sleep schedule should be avoided so treatment success is not jeopardized.

People with idiopathic hypersomnia should also avoid using depressant substances, such as alcohol, and other drugs that may cause drowsiness or impair one’s ability to function normally. Symptomatic individuals should avoid driving, operating machinery, or participating in activities that could result in injury. Those whose symptoms worsen or are non-responsive to treatment should seek additional medical attention.