Hypersomnia is a condition characterized by excessive sleepiness. It is an excessively deep or prolonged major sleep period. Hypersomnia may be associated with difficulty in awakening.  A person with hypersomnia might nap repeatedly during the day, often at inappropriate times such as at work, during a meal, or in conversation.

What causes hypersomnia?

The exact cause of hypersomnia is unknown. Researchers believe that it might be caused by another sleep disorder, dysfunction of the autonomic nervous system, tumor, head trauma, stress, a side effect of medication, or drug or alcohol abuse.


The most common symptoms are:

  • long periods of sleep
  • excessive sleepiness
  • excessive deep sleep
  • anxiety
  • decreased energy
  • loss of appetite
  • memory difficulty
  • hallucinations

Individuals with these symptoms may sleep-related problems, including a lack of energy and trouble thinking clearly.

How is hypersomnia diagnosed?

If you believe you have hypersomnia, contact your doctor. Your doctor will refer you to sleep specialist. The sleep specialist will order a sleep study. During a sleep study, you stay overnight while Technologists monitor your muscle movement, heartbeat, eye movement, leg movements and respiration. The specialist may also want to do a Multiple Sleep Latency Test. A Multiple Sleep Latency Test tests how sleepy you are.

Can hypersomnia be treated?

Yes. Treatment typically consists of behavioral changes, good sleep hygiene and taking stimulants to help you be more alert.

Sleep apnea?

If you also have sleep apnea, your doctor may prescribe a treatment known as continuous positive airway pressure, or CPAP. With CPAP, you wear a mask over your nose while you sleep. The mask is connected to a machine that delivers a continuous flow of air into the nostrils.