REM Behavior Disorder

Acting out dreams may lead to injury

A man dreams of fighting off a wild animal and wakes to find himself punching his wife in the arm. Another dreams of jumping over a hazard and wakes tumbling out bed and onto the floor. After throwing a punch out of sleep, a man reluctantly goes to his healthcare provider to get further evaluation. If you or a loved one have ever acted out dreams while remaining asleep, it could be a condition known as REM behavior disorder. What are the symptoms, causes, and treatments of this condition? Learn about how this disorder can be diagnosed and treated to prevent injury. 

Mature man sleeping in bed next to a pair of glasses
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During the night, we naturally progress through sleep stages, including rapid eye movement (REM) sleep. REM is normally characterized by intense brain activity and dreaming – and the inability to use our muscles, with the exception of our eye muscles and diaphragm (which allows us to breathe). REM sleep occurs periodically through the night, with the first period occurring about 90 minutes after sleep onset, lasting about 10 minutes. These periods become more prolonged as sleep progresses.

If our other muscles are not properly paralyzed, we may be able to perform complex activities and enact our dreams while we remain asleep. This is called REM behavior disorder. This disorder may lead to accidental injury, including injury of bed partners.


Most people with this disorder describe unpleasant and vivid dreams that involve intruders or attackers (people or animals). There is associated dream-enactment behavior that is often violent. Common behaviors include:

  • Talking or screaming
  • Reaching
  • Punching
  • Kicking
  • Jumping or falling out of bed
  • Running
  • Striking furniture

These behaviors frequently result in injury to the individual or their bed partner. The injuries may be minor (such as bruises, scratches, or cuts) or severe (such as broken bones or bleeding within the brain). People who are afflicted may complain of disrupted sleep or excessive daytime sleepiness.

REM behavior disorder affects about four or five people out of every 1,000. In about 90% of cases, it occurs in men who are in their 50s or 60s.


In most cases, a reported history of dream-enactment behaviors with a standard sleep study called a polysomnogram (PSG) will be sufficient to establish a diagnosis. The PSG will often show the abnormal presence of muscle tone (suggesting activity) during REM sleep, allowing the ability to inappropriately act out dreams. It is also important to document an absence of seizure-like electrical activity on the EEG because seizures can sometimes cause abnormal movements during sleep.

Imaging studies are typically normal in REM behavior disorder if there is no associated neurodegenerative disorder. However, the condition commonly occurs in the setting of other disorders.

Associated Conditions

REM behavior disorder is frequently associated with other neurologic disorders, and many patients will have another disorder like Parkinson’s disease, dementia with Lewy bodies, and multiple system atrophy.

Even when there is not an associated neurologic disorder at presentation, one study showed that up to 90.9% of patients with REM behavior disorder will go on to develop a neurodegenerative disease years or decades later. It has been suggested that REM behavior disorder may be a possible useful indicator for early prevention of these disorders. Not everyone develops these associated conditions.

There is a less frequent acute form of REM behavior disorder that may result from structural brain lesions such as a stroke, tumor, or in demyelination as may occur in multiple sclerosis. Another manifestation may also occur as the result of certain medications (including antidepressants and others that affect the brain), drug intoxication, or withdrawal from alcohol or sedative medications.

Other Disorders to Consider During Differential Diagnosis

There are a few other disorders that may have symptoms similar to REM behavior disorder and these must be considered. These are sometimes called pseudo-RBD. In general, these disorders may cause abnormal movements at night or excessive daytime sleepiness, and include:

These other causes of dream-enactment behaviors are not associated with the development of the other neurodegenerative disorders described above. Treatment is targeted toward the underlying cause instead.


In general, treatment of REM behavior disorder is focused on keeping the affected person and others safe. This involves making the bedroom a safe place by removing nightstands and sharp objects. In some cases, additional padding around the bed may be helpful. Some people need to lock the door or windows to keep themselves from getting into mischief. Once the movements are suppressed effectively with medication, fewer safety precautions may be necessary.

The medication clonazepam is a highly effective treatment for most patients. It can cause nighttime confusion in the elderly or daytime sleepiness, however, so this may make it intolerable to some. As an alternative, higher doses of melatonin has been demonstrated to be effective in a few small trials.

If you are concerned that you may have symptoms suggestive of REM behavior disorder, start by speaking with your healthcare provider and get the diagnosis and treatment that you need to stay safe during sleep.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Brandon Peters, MD
Brandon Peters, MD, is a board-certified neurologist and sleep medicine specialist.