The Cleveland Clinic

Insomnia: Symptoms and Causes

Insomnia is a sleep disorder that is characterized by difficulty falling and/or staying asleep. People with this sleep disorder have one or more of the following insomnia symptoms:

  • Difficulty falling asleep
  • Waking up often during the night and having trouble going back to sleep
  • Waking up too early in the morning
  • Feeling tired upon waking
  • Sleepiness during the day
  • Irritability and problems with concentration or memory

What Causes Insomnia?

Insomnia can be its own medical problem (primary insomnia) or it can be caused by a separate issue (secondary insomnia) such as depression or side effects from medication. Insomnia may be an acute (short-term) problem, meaning it lasts less than 1 month, or it can be chronic, lasting 1 month or longer.

Situations that may cause a period of acute insomnia can include:

  • Stress (for example, job loss or change, death of a loved one, divorce, or moving)
  • Illness
  • Emotional or physical discomfort
  • Environmental factors like noise, light, or extreme temperatures (hot or cold) that interfere with sleep
  • Some medications (for example those used to treat colds, allergies, depression, high blood pressure and asthma)
  • Interferences in normal sleep schedule (for example, jet lag or switching from a day to night shift)

Causes of chronic insomnia include:

  • Depression and/or anxiety
  • Chronic stress
  • Pain or discomfort at night

Reviewed by: The Sleep Medicine Center at The Cleveland Clinic.

Reviewed by Cynthia Dennison Haines, MD

SOURCES: The National Sleep Foundation. American Insomnia Association.


Last Editorial Review: 4/2/2007