Symptoms and causes

Symptoms

Sleep terrors differ from nightmares. The dreamer of a nightmare wakes up from the dream and may remember details, but a person who has a sleep terror episode remains asleep. Children usually don't remember anything about their sleep terrors in the morning. Adults may recall a dream fragment they had during the sleep terrors.

Sleep terrors generally occur in the first third to first half of the night, and rarely during naps. A sleep terror may lead to sleepwalking.

During a sleep terror episode, a person may:

  • Begin with a frightening scream or shout
  • Sit up in bed and appear frightened
  • Stare wide-eyed
  • Sweat, breathe heavily, and have a racing pulse, flushed face and dilated pupils
  • Kick and thrash
  • Be hard to awaken, and be confused if awakened
  • Be inconsolable
  • Have no or little memory of the event the next morning
  • Possibly, get out of bed and run around the house or have aggressive behavior if blocked or restrained

When to see a doctor

Occasional sleep terrors aren't usually a cause for concern. If your child has sleep terrors, you can simply mention them at a routine well-child exam. However, consult your doctor if sleep terrors:

  • Become more frequent
  • Routinely disrupt the sleep of the person with sleep terrors or other family members
  • Lead to safety concerns or injury
  • Result in daytime symptoms of excessive sleepiness or problems functioning
  • Continue beyond the teen years or start in adulthood

Causes

Sleep terrors are classified as a parasomnia — an undesirable behavior or experience during sleep. Sleep terrors are a disorder of arousal, meaning they occur during N3 sleep, the deepest stage of non-rapid eye movement (NREM) sleep. Another NREM disorder is sleepwalking, which can occur together with sleep terrors.

Various factors can contribute to sleep terrors, such as:

  • Sleep deprivation and extreme tiredness
  • Stress
  • Sleep schedule disruptions, travel or sleep interruptions
  • Fever

Sleep terrors sometimes can be triggered by underlying conditions that interfere with sleep, such as:

  • Sleep-disordered breathing — a group of disorders that include abnormal breathing patterns during sleep, the most common of which is obstructive sleep apnea
  • Restless legs syndrome
  • Some medications
  • Mood disorders, such as depression and anxiety
  • In adults, alcohol use

Risk factors

Sleep terrors are more common if family members have a history of sleep terrors or sleepwalking. In children, sleep terrors are more common in females.

Complications

Some complications that may result from experiencing sleep terrors include:

  • Excessive daytime sleepiness, which can lead to difficulties at school or work, or problems with everyday tasks
  • Disturbed sleep
  • Embarrassment about the sleep terrors or problems with relationships
  • Injury to oneself or rarely to someone nearby
July 21, 2017
References
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  2. Parasomnias. Merck Manual Professional Version. http://www.merckmanuals.com/professional/neurologic-disorders/sleep-and-wakefulness-disorders/parasomnias. Accessed May 10, 2017.
  3. Non-rapid eye movement sleep arousal disorders. In: Diagnostic and Statistical Manual of Mental Disorders DSM-5. 5th ed. Arlington, Va.: American Psychiatric Association; 2013. http://dsm.psychiatryonline.org. Accessed May 9, 2017.
  4. AskMayoExpert. Parasomnias. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2016.
  5. Kotagal S. Sleepwalking and other parasomnias in children. https://www.uptodate.com/home. Accessed May 10, 2017.
  6. Foldvary-Schaefer N. Disorders of arousal from non-rapid eye movement sleep in adults. https://www.uptodate.com/home. Accessed May 10, 2017.
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