Causes and Diagnoses

Causes and Diagnoses of Parasomnias

Parasomnias often run in families, so there may be a genetic factor. Brain disorders may also be responsible for some parasomnias, such as some cases of REM sleep behavior disorder. Parasomnias can also be triggered by other sleep disorders, such as obstructive sleep apnea and various medications.

Parasomnias affect approximately 10 percent of Americans. They occur in people of all ages, but are most common in children. Children are particularly vulnerable because of brain immaturity. The good news is they are usually not associated with negative health consequences and disappear as the child matures.


In order to determine what is causing your parasomnia, a sleep medicine specialist will often ask you to complete a sleep diary for two weeks. This will give the specialist clues as to what might be causing your problems. You can also rate your sleep with the Epworth Sleepiness Scale. This will help show how your sleep is affecting your daily life. The sleep medicine specialist will need to know your complete medical history. Make sure to tell the physician of any past or present medications and if you have ever had any other sleep disorder.

A sleep medicine specialist will try to determine if there is something else that is causing your parasomnia or making the symptoms worse, such as:

  • Another sleep disorder
  • A medical condition
  • Medication use
  • A mental health disorder
  • Substance abuse

The sleep medicine specialist may want to examine your sleep using an in-lab sleep study. Also known as a polysomnogram, a sleep study charts your brain waves, heart beat and breathing as you sleep. It also looks at how your arms and legs move and records your behavior during sleep on video. This will help show if you get out of bed and do anything unusual during your sleep study.

If you think you have a parasomnia and it is interfering with your ability to sleep, schedule an appointment with a board-certified sleep medicine specialist at Northwestern Medicine. If there is risk of injury to yourself or others from your parasomnia, seek immediate medical attention.

Related Resources

The National Sleep Foundation offers information on sleep and parasomnias.