REM Sleep Behavior Disorder Explained

Medically Reviewed By Nick Villalobos, MD
Was this helpful?

REM sleep behavior disorder is a condition that causes sleepers to move, shout, and act out their dreams during their REM sleep. Certain medications and antidepressants may trigger REM sleep behavior disorder as well as some underlying conditions, such as narcolepsy and other neurodegenerative disorders.

Doctors can help you manage REM sleep behavior disorder with appropriate treatment. You can also improve your symptoms and reduce the frequency of episodes by making some lifestyle adjustments.

This article will explain what REM sleep behavior disorder is as well as its symptoms, treatment, and potential complications.

What is REM sleep behavior disorder?

Shirtless man waking up in bed with hand on face
HEX/Getty Images

Rapid eye movement (REM) sleep is a phase of sleep marked by increased heart rate, brain activity, and eye movement. The REM sleep phase usually starts about 90 minutes after you fall asleep. You may have dreams occurring during REM sleep.

During the REM phase, your muscles usually go through a state of temporary paralysis. This does not happen in a person with REM sleep behavior disorder. People with this condition have incomplete or totally absent muscle paralysis. This may lead them to act out their dreams, sometimes in violent or dramatic ways.

REM sleep behavior disorder is a rare condition that occurs in about 1% of the population.

REM sleep behavior disorder causes sleepers to move their limbs in bed and engage in actions linked to being awake. If you have this condition, you may injure yourself and whoever is in bed with you. You may become violent if you’re aggressive or frightened in your dream.

If you wake up, you may remember your dream but you’ll have no idea that you moved or engaged in any action.

People usually have around four REM phases per night. REM sleep behavior disorder episodes are more frequent in the morning REM phase, but they can occur in any REM phase during your sleep.

Learn more about common sleep disorders.

What causes REM sleep behavior disorder?

Doctors do not know the exact cause of REM sleep behavior disorder. So far, it’s believed that anything that affects the regular inhibition of muscle movement during REM sleep can lead to the condition. This includes problems in the nervous system itself as well as substances that might disrupt the pathway.

Experts categorize REM sleep behavior disorder as:

  • idiopathic: due to an unidentified factor
  • drug-induced: due to a substance or medication
  • secondary: due to another neurological condition

Someone can develop REM sleep behavior disorder many years before a diagnosis of a neurodegenerative condition, particularly one associated with Lewy bodies.

Lewy bodies are unusual aggregates of a protein known as alpha-synuclein. Lewy bodies are associated with:

What are the risk factors for REM sleep behavior disorder?

Possible factors that may raise someone’s chances of developing REM sleep behavior disorder include:

  • alcohol withdrawal
  • antidepressant use
  • depression
  • post-traumatic stress disorder (PTSD)
  • being assigned male at birth
  • smoking
  • narcolepsy
  • brain injury

Socioeconomic factors that may elevate someone’s chances of having REM sleep behavior disorder include:

  • inequities in access to care
  • having a low education level

What medications can cause REM sleep behavior disorder?

Selective serotonin reuptake inhibitors (SSRIs) are the most common medication to cause REM sleep behavior disorder. These antidepressants counteract REM-mediated paralysis, inciting muscle tone instead.

SSRIs include:

Other medications that have been shown to cause REM sleep behavior disorder include:

  • tricyclic antidepressants
  • cholinesterase inhibitors for Alzheimer’s disease such as:
    • rivastigmine (Exelon)
    • galantamine (Razadyne)
    • donepezil (Aricept)
  • mirtazapine (Remeron) in the treatment of parkinsonism, per older case reports
  • venlafaxine (Effexor), per a 2017 case report
  • monoamine oxidase inhibitors

What are the symptoms of REM sleep behavior disorder?

The symptoms of REM sleep behavior disorder may include:

  • shouting and screaming
  • talking
  • punching or kicking
  • cursing
  • lashing out physically
  • sleepwalking
  • an ability to recall dreams clearly

All symptoms occur during the REM stage of sleep.

Learn about sleep disorder signs and symptoms.

How do doctors diagnose REM sleep behavior disorder?

Your doctor will review your medical history and ask about your symptoms before they can make an REM sleep behavior disorder diagnosis. The tests they will use to evaluate your condition include:

  • Polysomnogram: Also known as a sleep study, you spend a night in a sleep lab where a healthcare professional monitors your lungs, brain, and heart activity. They will also check your limb movements and vocalizations while you are asleep, and may videotape your REM cycles.
  • Neurological and physical exam: Your doctor will conduct exams to evaluate potential REM sleep behavior disorder and other atypical sleep behaviors. REM sleep behavior disorder may coexist with other sleep disturbances such as narcolepsy and sleep apnea.

If you live with someone else or have a sleeping partner, your doctor may ask them about your sleep behavior. They may ask them to fill out a questionnaire.

To diagnose REM sleep behavior disorder, doctors usually follow the International Classification of Sleep Disorders, Third Edition (ICSD-3). The criteria include:

  • repeatedly talking and performing complex motor behavior such as punching and kicking
  • REM sleep without atonia, recorded by the sleep study as an elevation of motor tone in the chin or limbs
  • absence of epileptic activity during REM sleep unless the doctor can clearly distinguish REM sleep behavior disorder from a co-occurring REM-related seizure disorder
  • behavior not explained by a mental health condition, substance use disorder, or medication

It may take time to confirm a diagnosis of REM sleep behavior disorder, especially in children. According to research, non-REM sleep disturbances can mimic REM sleep behavior disorder. These include sleepwalking and sleep terrors.

What are the treatment options for REM sleep behavior disorder?

If your doctor identifies a specific cause of your REM sleep behavior disorder, treatment will initially focus on treating that issue. For example, if a medication is causing REM sleep behavior disorder, discontinuing or reducing the dose may resolve your symptoms.

The effectiveness of REM sleep behavior disorder treatments may depend on the cause.

In addition to addressing any potential underlying causes, your doctor may prescribe a low dose of clonazepam (Klonopin). Clonazepam is a benzodiazepine which is sedating. This medication may help relax your body while you’re asleep and reduce your muscle activity. This type of treatment generally has a good outcome.

If clonazepam is not effective, your doctor may suggest melatonin.

Avoiding alcohol may help reduce your symptoms or lower their frequency.

To avoid injuries to yourself or others, you may also need to adjust your sleeping environment, such as:

  • sleeping alone
  • lowering the bed to the floor
  • removing or padding nearby furniture
  • installing a bed alarm

What is the outlook for REM sleep behavior disorder?

REM sleep behavior disorder episodes may grow more violent if the condition is left untreated. Treatment is important to prevent injuries.

The outlook depends on the cause and severity of the condition.

People with REM sleep behavior disorder may develop emotional, cognitive, and neurological problems such as:

  • anxiety
  • apathy
  • lower attention
  • problems with executive functioning

Some people with REM sleep behavior disorder may also develop Parkinson’s disease or other neurological conditions. Treatment may then involve treating both REM sleep behavior disorder and the co-occurring condition.

Other complications may include injuring yourself or your sleeping partner.

Other frequently asked questions

Nick Villalobos, M.D., reviewed the following questions.

Is REM sleep behavior disorder a mental illness?

REM sleep behavior disorder is not a mental illness. It is a sleep disorder. Doctors associate it with psychiatric conditions only in rare cases.

How serious is REM sleep behavior disorder?

REM sleep behavior disorder may be a sign of someone developing a neurodegenerative condition, such as Parkinson’s disease. If you develop REM sleep behavior disorder symptoms, consider contacting your doctor for an evaluation.

Read 10 Things You Didn’t Know About Your Sleep.


REM sleep behavior disorder is a condition where your muscle movements are not fully switched off during your REM sleep. People with this condition may start shouting, punching, and kicking while they are asleep. This can be harmful to them and to their sleeping partners.

REM sleep behavior disorder requires diagnosis and treatment, as an underlying condition may be its cause. Dedicated sleep centers help doctors diagnose REM sleep behavior disorder. Then, doctors may prescribe medications to treat the condition.

REM sleep behavior disorder is a risk factor for neurodegenerative conditions, such as Parkinson’s disease and Lewy body dementia.

Was this helpful?
Medical Reviewer: Nick Villalobos, MD
Last Review Date: 2022 Oct 31
View All Sleep Disorders Articles
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.