What Is Hypersomnia?

Everybody knows about insomnia, and most people have suffered through sleepless nights. But, did you know that insomnia has an evil twin called hypersomnia? Insomnia keeps you awake at night. Hypersomnia put you to sleep during the day, even if you sleep all night.

hypersomnia symptoms tired everywhere

Unlike insomnia which keeps you up all day, hypersomnia symptoms include naps or sleep attacks throughout the day that don't leave you feeling well-rested.

© Image Source | Getty Images

According to the National Institute of Neurological Disorders and Stroke (NINDS), hypersomnia is recurring and severe episodes of daytime sleepiness or prolonged sleeping at night. Daytime sleepiness may cause an irresistible lapse into daytime napping, sometimes without warning, called sleep attacks. After waking up from a nap or sleep attack, people with hypersomnia may feel drugged or brain fogged, called sleep drunkenness.

Hypersomnia can interfere with your ability to function at home, work, or school. A nap or sleep attack while driving or operating dangerous machinery can be life-threatening. In fact, hypersomnia may be responsible for one out of five motor vehicle accidents.

Hypersomnia has been recognized as a medical problem for a long time. In the 17th Century, it was described as patients with a sleepy disposition who suddenly fall fast asleep. About 30 percent of people complain of excessive daytime sleepiness today. About five percent of the population may be diagnosed with hypersomnia. Hypersomnia is usually diagnosed between the ages of 17 and 24, and is more common in women.

Symptoms of Hypersomnia

According to the Diagnostic and Statistical Manual of Mental Disorders, to diagnose hypersomnia you need to experience excessive sleepiness despite getting at least seven hours of sleep and lapse into naps several times each day, or sleep more than 9 hours at night and still feel sleepy, or experience sleep drunkenness. These symptoms must occur at least three times per week for at least three months. The symptoms must be severe enough to interfere with your function at home, work, or school. Other symptoms may include:

  • Naps or sleep attacks that don’t improve sleepiness
  • Feeling anxious, restless, depressed, or irritable
  • Having very little energy
  • Slowed thinking or speech
  • Poor memory
  • Frequent headaches
  • Loss of appetite

Causes of Hypersomnia

Causes of hypersomnia are divided into secondary and primary causes. Secondary causes are excessive daytime sleepiness caused by another disease. In these cases, hypersomnia is one of the symptoms of another condition. These conditions include:

  • Sleep apnea
  • Drug or alcohol abuse
  • Side effects from prescription drugs
  • Depression or bipolar disorder
  • Obesity
  • Parkinson’s disease
  • Multiple Sclerosis
  • Brain tumor or head trauma
  • Hypothyroidism
  • Epilepsy
  • Long-term sleep deprivation

Primary hypersomnia is hypersomnia caused by a specific condition in which excessive sleepiness is the main symptom. There are three causes of primary hypersomnia:

  • Idiopathic hypersomnia is hypersomnia of an unknown cause. This condition may be due to a genetic defect passed down through families, since 39 percent of people have a family history.
  • Narcolepsy is a disease caused by low levels of the brain messenger (neurotransmitter) hypocretin. This neurotransmitter helps control waking up from sleep. Narcolepsy causes symptoms of hypersomnia and may also cause sudden loss of muscle tone triggered by strong emotions, called cataplexy. It may also cause hallucinations and sleep paralysis when falling asleep or waking up.
  • Kleine-Levin syndrome is a rare condition that causes recurring episodes of sleeping for up to 20 hours along with increased appetite and other abnormal behaviors. Episodes can last for days or weeks. Between episodes sleep and other behaviors return to normal. Episodes may be triggered by alcohol use or an infection. The cause is unknown and episodes tend to decrease with older age.

Diagnosis and Treatment

Diagnosis of hypersomnia is based on the symptoms, sleep studies, and brain wave studies. Treatment depends on the cause. Hypersomnia caused by another disease may improve when that condition is treated, such as thyroid replacement for hypothyroidism or continuous positive airway pressure (CPAP) for sleep apnea.

A new medication was recently approved to treat idiopathic hypersomnia called Xywav, it contains the minerals calcium, magnesium, and potassium along with a narcolepsy medication called sodium oxybate. Other medications may include stimulant drugs, Parkinson’s disease drugs, wakefulness drugs, and antidepressants. Along with medications, good sleep habits and the avoidance of the stimulants caffeine, nicotine, and alcohol are helpful. Some patients improve with planned naps during the day.

Although not a fatal disease, untreated hypersomnia can be difficult to live with, affect your quality of life, and can even be dangerous. Most cases of hypersomnia tend to be long-term conditions. Let your doctor know if you have any of the symptoms of hypersomnia. Medications can help.


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Chris Iliades, MD

Dr. Chris Iliades is board-certified in Ear, Nose and Throat and Head and Neck Surgery from the American Board of Otolaryngology and Head and Neck Surgery. He holds a medical … Read More

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