Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at July 28, 2016

An individual who cannot stay awake during the day may suffer from a sleep disorder. While classified in different ways, hypersomnia or hypersomnolence is characterized by excessive daytime sleepiness and can be a debilitating disorder that impairs the quality of an individual's life.


Definition & Facts

Hypersomnia may be symptomatic of another disease or it can be a primary condition. It is alternately defined as a mental disorder, a neurological disorder and a sleep disorder. Narcolepsy, idiopathic hypersomnia, Kleine-Levin syndrome, and posttraumatic hypersomnia are considered types of hypersomnia. However, hypersomnolence disorder is also defined by the Diagnostic and Statistical Manual of Mental Disorders as distinct from narcolepsy and other sleep disorders.

Hypersomnia not only puts jobs and relationships at risk, it could be responsible for close to 1,550 deaths and 71,000 injuries due to automobile accidents. Difficulty thinking clearly, persistent lethargy, and the risk of falling asleep at any time during the day are characteristics of hypersomnia.

The National Sleep Foundation estimates that up to 40% of individuals could suffer from excessive tiredness or hypersomnia from time to time. However, primary hypersomnia is exceedingly rare and affects less than 1% of the population.

Symptoms & Complaints 

Hypersomnolence presents as excessive daytime sleepiness or difficulty waking from an amount of sleep that would be adequate for healthy individuals. It is most often found in adolescents and young adults.

Symptoms can include feelings of disorientation or confusion. There are more symptoms that often accompany the condition as well, and they include:


In some cases, the condition affects those who are genetically predisposed to it in which case it is considered primary hypersomnia. A complex interaction of socioeconomic factors, environmental factors, and genetics all may play a role in causing primary hypersomnia.

Hypersomnia more often manifests itself as a consequence of other disorders. One of the most common causes of secondary hypersomnolence is sleep apnea, a condition in which a person actually stops breathing during sleep. The pause in breathing typically lasts from a few seconds to a few minutes before the person begins breathing again. Sleep apnea affects men more than women.

Other sleep disorders like sleep deprivation, sleeping sickness (associated with an illness or infection), sleepwalking, night terrors, bedwetting and restless legs syndrome are also responsible for disrupting sleep and can cause a person to present the symptoms of hypersomnia.

Prescription drugs such as tranquilizers and antihistamines can contribute to the condition either on an acute or long-term basis depending upon the strength of dosage or how long those medications are taken. Head injuries or other neurological disorders like multiple sclerosis or Parkinson’s disease can also contribute to hypersomnia.

Depression often contributes to or presents itself with the very same symptoms that persons suffering from hypersomnolence complain of and is therefore seen as a possible cause or related condition as well. Being severely overweight or obese can be a related cause of the condition as can the abuse of drugs, alcohol use disorder, and excessive caffeine consumption.

Diagnosis & Tests 

There are criteria that must be met in order for a person to be specifically diagnosed with the condition. One must experience symptoms for at least a month to be diagnosed with acute hypersomnia. Dealing with hypersomnia for at least three months may be described as persistent hypersomnia.

Additional symptoms of primary hypersomnia as defined by the Diagnostic and Statistical Manual of Mental Disorders include the following:

  • Sleepiness must cause significant impairment of social, occupational or educational function.
  • Sleepiness cannot be accounted for by an inadequate amount of sleep or is unrelated to any other sleeping disorders.
  • Sleepiness is not related to a physiological response to either a prescription medication or the abuse of another substance such as drugs and alcohol.

Most tests for diagnosing hypersomnia serve the function of ruling out the long list of other conditions in which hypersomnia presents itself as a symptom rather than its own cause. For that reason, sleep studies, blood tests, computed tomography (CT) scans, and EEGs are used to help identify other possible causes. A history of head trauma, central nervous system injuries, or tumors are also brought into consideration when ruling out possible causes of the specific condition.

Treatment & Therapy 

Treatment of hypersomnia is most often related to the treatment of the other conditions of which hypersomnia is a symptom. In cases where sleep apnea is diagnosed as the underlying cause, physicians often prescribe continuous positive airway pressure or CPAP treatments. CPAP machines use air to keep constant pressure on the obstructions that tend to block the airways causing apnea. The patient wears a mask while sleeping in order for air to be pushed into the nostrils and into the back of the throat.

Hypersomnia conditions that are brought on by substances such as drugs, alcohol or even caffeine will be addressed by cutting said substances out of the diet. Additionally, prescription drugs that might be the cause of the condition are exchanged for medications that will not contribute to the condition. Where head trauma, neurological disorders or other diseases are the cause, the treatment of those diseases or conditions will be undertaken and hypersomnolence symptoms addressed. For those who struggle with hypersomnia that is associated with depression, psychotherapy such as cognitive behavior therapy may help.

Where hypersomnia alone is the cause, doctors often prescribe stimulants such as those used in the treatment of ADHD like amphetamines in order to help sustain alertness in individuals suffering from the condition throughout the day. In addition, doctors often prescribe activating antidepressants, levodopa, monoamine oxidase inhibitors, bromocriptine, and clonidine.

Prevention & Prophylaxis 

Behavioral changes can be helpful in regulating an individual’s sleep schedule so as to promote the best day-to-day functioning. Avoiding late-night work and social activities which delay getting to bed on time can significantly contribute to the prevention of hypersomnia.

Avoiding the ingestion of alcohol and/or caffeine in the hours close to bedtime or avoiding certain foods that might keep a person awake at night can also contribute to prevention of the condition.

To the extent that secondary hypersomnia is caused by sleep apnea and to the extent that sleep apnea is caused by obesity, adopting a healthy diet and regular exercise that promote the maintenance of a healthy weight will reduce the likelihood of hypersomnia.