definition: What is Hypersomnia?

Hypersomnia, as a sleep disorder, is characterized by excessive daytime sleepiness. In other words, it is the tendency to fall asleep repeatedly during the day despite having an apparently sufficient amount of nighttime sleep—but one that is not refreshing for the hypersomniac. As a result, the person constantly feels the need to sleep throughout the day.
There are two types of hypersomnia: primary and secondary.

Hypersomnia should not be confused with insomnia, which refers to a lack of sleep caused by difficulty falling asleep or staying asleep during the night, for various reasons.

What Are the Types of Hypersomnia?

What is Primary or Central Hypersomnia?

Primary or central hypersomnia is a rare form of the disorder. It is more difficult to explain because it is not directly linked to another condition such as sleep apnea or another medical disorder.

It is characterized by significant sleepiness, along with daytime naps—long naps that do not restore energy.
There are three main types:

• Narcolepsy
• Idiopathic hypersomnia
• Recurrent hypersomnia

What is Idiopathic Hypersomnia?

Idiopathic hypersomnia is a chronic disorder manifested by excessive daytime sleepiness. Even after a “good night’s sleep,” people with this rare condition have great difficulty waking up. In this form of hypersomnia, the patient does not suffer from cataplexy (sudden loss of muscle tone).

What is Recurrent Hypersomnia or Kleine-Levin Syndrome?

Kleine-Levin Syndrome involves recurrent episodes of excessive sleepiness that may last several days or even weeks. This condition most often affects males. Between episodes, sleep returns to “normal.” As the person ages, these episodes may diminish.

What is Secondary Hypersomnia?

Secondary hypersomnia is associated with another medical condition or external factor (unlike primary hypersomnia). It is also characterized by excessive daytime sleepiness that can affect quality of life and daily relationships.

What Causes Hypersomnia?

Causes of Primary Hypersomnia

Primary hypersomnia may be linked to behavioral, cognitive, or psychiatric disorders. However, the exact causes are complex and often uncertain.

Causes of Secondary Hypersomnia

Secondary hypersomnia can result from various factors or medical conditions, such as:

• Sleep-related breathing disorders (e.g., obstructive sleep apnea, upper airway resistance syndrome);
• Neurological disorders such as epilepsy or Parkinson’s disease;
• Psychiatric disorders such as depression or bipolar disorder;
• Use of certain medications, including antidepressants, sedatives, or hypnotics;
• Certain medical conditions, such as hyperthyroidism.

What Are the Symptoms and Consequences of Hypersomnia?

The symptoms of hypersomnia vary and may include:

• Excessive daytime sleepiness;
• Difficulty waking up in the morning, with trouble getting out of bed even after many hours of rest;
• Problems with concentration, affecting school or professional performance;
• Episodes of sleep paralysis;
• Hallucinations;
• Uncontrollable sleep attacks, i.e., sudden, irresistible episodes of falling asleep at inappropriate times.

These may occur suddenly and involuntarily. There may also be cataplexy, a sudden loss of muscle tone often triggered by strong emotions.

How Is Hypersomnia Diagnosed?

Diagnosis is made using a Multiple Sleep Latency Test (MSLT), which measures how quickly a patient falls asleep in a quiet, comfortable environment during the day. This test helps confirm the diagnosis and determine the type of hypersomnia.
Additional tests may include an alertness test or polysomnography.

What Are the Treatments for Hypersomnia?

There is no specific treatment for hypersomnia. If an underlying cause is identified, treatment will target that cause.
In practice, doctors may prescribe stimulant medications to promote wakefulness and reduce daytime sleepiness.

How Can Hypersomnia Be Prevented?

There are no definitive preventive measures. However, maintaining a healthy lifestyle can help reduce the risk of developing symptoms related to this sleep disorder. For example:

• Avoid frequent use of alcohol or other substances;
• Follow a balanced and healthy diet, as digestion and food choices can influence sleep quality.

Living with Hypersomnia

Managing hypersomnia on a daily basis can be difficult. It may affect productivity, concentration, and even safety—especially when driving or operating machinery.
Nevertheless, treatments and medical support are available to help people with hypersomnia improve their quality of life.

It is provided for informational purposes only and should not replace professional medical advice. Only your physician can make a diagnosis.

To receive an accurate diagnosis tailored to your personal situation—or to learn more about your condition—you should always consult a qualified doctor.